/* AI Tutor - Styles
   Updated: 2026-01-13
   ============================================================ */

/* ============================================================
   Variables
   ============================================================ */
:root {
    --primary: #2563eb;
    --primary-hover: #1d4ed8;
    --primary-light: #dbeafe;

    --gray-50: #f9fafb;
    --gray-100: #f3f4f6;
    --gray-200: #e5e7eb;
    --gray-300: #d1d5db;
    --gray-400: #9ca3af;
    --gray-500: #6b7280;
    --gray-600: #4b5563;
    --gray-700: #374151;
    --gray-800: #1f2937;
    --gray-900: #111827;

    --success: #10b981;
    --danger: #ef4444;

    --radius-sm: 4px;
    --radius: 8px;
    --radius-lg: 12px;

    --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
    --shadow-lg: 0 10px 15px rgba(0,0,0,0.1), 0 4px 6px rgba(0,0,0,0.05);

    --font: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;

    --container-width: 1200px;
    --sources-width: 300px;
}

/* ============================================================
   Reset
   ============================================================ */
*, *::before, *::after { box-sizing: border-box; }

html {
    overflow-y: scroll;
}

body {
    margin: 0;
    font-family: var(--font);
    font-size: 14px;
    line-height: 1.5;
    color: var(--gray-800);
    background-color: white;
    background-image:
        linear-gradient(var(--gray-200) 1px, transparent 1px),
        linear-gradient(90deg, var(--gray-200) 1px, transparent 1px);
    background-size: 12px 12px;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
}

h1, h2, h3, h4 { margin: 0; font-weight: 600; }
p { margin: 0 0 1rem 0; }
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

.panel-hidden { display: none !important; }
.text-muted { color: var(--gray-500); }

/* ============================================================
   Buttons
   ============================================================ */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 8px 16px;
    font-size: 14px;
    font-weight: 500;
    border: none;
    border-radius: var(--radius);
    cursor: pointer;
    transition: all 0.15s;
}

.btn-primary {
    background: var(--primary);
    color: white;
}
.btn-primary:hover { background: var(--primary-hover); }

.btn-secondary {
    background: white;
    color: var(--gray-700);
    border: 1px solid var(--gray-300);
}
.btn-secondary:hover { background: var(--gray-50); border-color: var(--gray-400); }

.btn-danger {
    background: white;
    color: var(--danger);
    border: 1px solid var(--danger);
}
.btn-danger:hover { background: var(--danger); color: white; }

.btn-link {
    background: none;
    border: none;
    color: var(--gray-600);
    padding: 4px 8px;
}
.btn-link:hover { color: var(--primary); text-decoration: underline; }

.btn-small {
    padding: 6px 12px;
    font-size: 13px;
}

.btn-close {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    padding: 0;
    background: transparent;
    border: none;
    border-radius: var(--radius);
    color: var(--gray-400);
    cursor: pointer;
    font-size: 24px;
    line-height: 1;
    transition: all 0.15s;
}
.btn-close:hover { background: var(--gray-100); color: var(--gray-600); }

.btn-group {
    display: flex;
    gap: 8px;
    margin-top: 16px;
}

/* ============================================================
   Forms
   ============================================================ */
.form-group { margin-bottom: 16px; }
.form-group label {
    display: block;
    margin-bottom: 6px;
    font-size: 13px;
    font-weight: 500;
    color: var(--gray-700);
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.form-hint {
    margin-top: 4px;
    font-size: 12px;
    color: var(--gray-500);
}

input[type="text"],
input[type="email"],
input[type="password"],
input[type="file"],
select,
textarea {
    width: 100%;
    padding: 10px 12px;
    font-size: 14px;
    font-family: var(--font);
    color: var(--gray-800);
    background: white;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius);
    transition: border-color 0.15s, box-shadow 0.15s;
}

input:focus, select:focus, textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}

input::placeholder, textarea::placeholder { color: var(--gray-400); }

textarea { resize: vertical; min-height: 120px; }

/* ============================================================
   App Container - 1200px centered
   ============================================================ */
.app-container {
    max-width: var(--container-width);
    margin: 0 auto;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    background: white;
    box-shadow: 0 0 40px rgba(0,0,0,0.1);
}

/* ============================================================
   App Footer
   ============================================================ */
.app-footer {
    text-align: center;
    padding: 12px 24px;
    background: white;
    color: var(--gray-500);
    font-size: 13px;
    border-top: 1px solid var(--gray-200);
}

/* ============================================================
   App Header - Logo left, user right (white bg, dark text)
   ============================================================ */
.app-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 24px;
    height: 86px;
    max-height: 86px;
    min-height: 86px;
    box-sizing: border-box;
    background: white;
    color: var(--gray-800);
    border-bottom: 1px solid var(--gray-200);
}

.header-left {
    width: 120px;
    flex-shrink: 0;
}

.header-logo {
    height: 62px;
    max-height: 62px;
    width: auto;
    object-fit: contain;
}

.app-header h1 {
    font-size: 22px;
    color: var(--gray-800);
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 12px;
}

.user-name {
    font-size: 14px;
    color: var(--gray-600);
}

.app-header .btn-link {
    color: var(--gray-500);
}
.app-header .btn-link:hover {
    color: var(--primary);
}

/* ============================================================
   App Navigation Icons (in header)
   ============================================================ */
.app-nav {
    display: flex;
    gap: 9px;
    align-items: center;
    justify-content: flex-end;
    flex: 1;
    padding-right: 20px;
    margin-right: 20px;
    border-right: 4px solid var(--gray-300);
}

.nav-icon {
    padding: 0 6px;
    padding-bottom: 8px;
    border: none;
    background: transparent;
    cursor: pointer;
    transition: all 0.15s;
    display: flex;
    align-items: center;
    justify-content: center;
    border-bottom: 4px solid transparent;
    position: relative;
}

.nav-icon.active {
    border-bottom: 4px solid var(--primary);
}

.nav-icon:hover:not(.active) {
    border-bottom: 4px solid var(--gray-300);
}

.nav-icon img {
    height: 45px;
    width: auto;
    object-fit: contain;
}

/* Nav Dropdown (More Classes) */
.nav-dropdown-container {
    position: relative;
    display: inline-block;
}

.nav-dropdown-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 50%;
    transform: translateX(-50%);
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    z-index: 1000;
    min-width: 160px;
    padding: 8px 0;
    margin-top: 4px;
}

.nav-dropdown-container.open .nav-dropdown-menu {
    display: block;
}

.nav-dropdown-item {
    display: flex;
    align-items: center;
    gap: 10px;
    width: 100%;
    padding: 10px 16px;
    border: none;
    background: transparent;
    cursor: pointer;
    font-size: 14px;
    color: var(--gray-700);
    transition: background 0.15s;
    text-align: left;
}

.nav-dropdown-item:hover {
    background: var(--gray-100);
}

.nav-dropdown-item img {
    height: 28px;
    width: auto;
}

.nav-dropdown-item span {
    font-weight: 500;
}

/* Tippy.js tooltip styling */
.tippy-box[data-theme~='aitutor'] {
    background: #ffffff;
    color: var(--primary);
    border: 2px solid #000000;
    border-radius: 10px;
    box-shadow: 0 4px 14px rgba(0, 0, 0, 0.15);
    font-weight: 500;
}

.tippy-box[data-theme~='aitutor'] .tippy-content {
    padding: 8px 14px;
}

.tippy-box[data-theme~='aitutor'] .tippy-arrow {
    color: #000000;
}

.tippy-box[data-theme~='aitutor'] .tippy-arrow::before {
    border-bottom-color: #000000;
}

/* Profile icon - right justified, no underline */
.header-profile {
    width: 120px;
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: flex-end;
    padding-right: 16px;
}

.nav-icon-profile {
    padding: 0;
    border: none;
    background: none;
    background-color: transparent;
    cursor: pointer;
    transition: opacity 0.15s;
    display: flex;
    align-items: center;
    justify-content: center;
    outline: none;
    -webkit-appearance: none;
    appearance: none;
}

.nav-icon-profile:hover {
    opacity: 0.8;
}

.nav-icon-profile img {
    height: 45px;
    width: auto;
    object-fit: contain;
}

/* ============================================================
   App Screens
   ============================================================ */
.app-screen {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

/* ============================================================
   Schedule Screen Layout
   ============================================================ */
.schedule-layout {
    display: flex;
    flex: 1;
    overflow: hidden;
}

.schedule-left {
    width: 35%;
    min-width: 280px;
    max-width: 50%;
    display: flex;
    flex-direction: column;
    background: white;
    border-right: 1px solid var(--gray-200);
}

.schedule-resizer {
    width: 6px;
    background: var(--gray-100);
    cursor: col-resize;
    transition: background 0.15s;
    flex-shrink: 0;
}

.schedule-resizer:hover,
.schedule-resizer.dragging {
    background: var(--primary);
}

.schedule-right {
    flex: 1;
    min-width: 400px;
    display: flex;
    flex-direction: column;
    background: var(--gray-50);
    overflow: hidden;
}

/* Assignments Panel */
.schedule-assignments {
    display: flex;
    flex-direction: column;
    height: 100%;
}

.assignments-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 20px;
    border-bottom: 1px solid var(--gray-200);
    background: white;
}

.assignments-header h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--gray-800);
    margin: 0;
}

.assignments-filters {
    padding: 12px 20px;
    border-bottom: 1px solid var(--gray-100);
    background: var(--gray-50);
}

.assignments-filters select {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    background: white;
    font-size: 14px;
    color: var(--gray-800);
}

.assignments-list {
    flex: 1;
    overflow-y: auto;
    padding: 12px;
}

.assignments-list .empty-state {
    text-align: center;
    padding: 40px 20px;
    color: var(--gray-700);
}

.assignments-list .empty-state p {
    margin: 0 0 8px;
}

.assignments-list .text-muted {
    font-size: 13px;
    color: var(--gray-600);
}

/* Assignment Item */
.assignment-item {
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    padding: 12px 16px;
    margin-bottom: 8px;
    cursor: pointer;
    transition: all 0.15s;
}

.assignment-item:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-sm);
}

.assignment-item.selected {
    border-color: var(--primary);
    background: var(--primary-light);
}

.assignment-item-title {
    font-weight: 500;
    color: var(--gray-800);
    margin-bottom: 4px;
}

.assignment-item-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 12px;
    color: var(--gray-700);
}

.assignment-item-due {
    display: flex;
    align-items: center;
    gap: 4px;
}

.assignment-item-due.overdue {
    color: var(--danger);
}

.assignment-status {
    display: inline-block;
    padding: 2px 8px;
    border-radius: 10px;
    font-size: 11px;
    font-weight: 500;
}

.assignment-status.pending {
    background: var(--gray-100);
    color: var(--gray-600);
}

.assignment-status.in_progress {
    background: #DBEAFE;
    color: #1E40AF;
}

.assignment-status.completed {
    background: #D1FAE5;
    color: #065F46;
}

.assignment-status.overdue {
    background: #FEE2E2;
    color: #991B1B;
}

/* Calendar Container */
.calendar-container {
    display: flex;
    flex-direction: column;
    height: 100%;
}

.calendar-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 20px;
    background: white;
    border-bottom: 1px solid var(--gray-200);
    gap: 16px;
}

.calendar-nav {
    display: flex;
    align-items: center;
    gap: 8px;
}

.calendar-header h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--gray-800);
    margin: 0;
    min-width: 160px;
    text-align: center;
}

.calendar-views {
    display: flex;
    gap: 4px;
}

.btn-view {
    padding: 6px 12px;
    font-size: 13px;
    background: transparent;
    border: 1px solid var(--gray-200);
    color: var(--gray-800);
    border-radius: var(--radius);
    cursor: pointer;
    transition: all 0.15s;
}

.btn-view:hover {
    background: var(--gray-50);
    border-color: var(--gray-300);
}

.btn-view.active {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
}

.btn-icon {
    padding: 6px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--gray-800);
    transition: all 0.15s;
}

.btn-icon:hover {
    background: var(--gray-50);
    border-color: var(--gray-300);
    color: var(--gray-800);
}

.calendar-body {
    flex: 1;
    overflow-y: scroll;
    padding: 16px;
}

/* Calendar Day View */
.calendar-day-view {
    background: white;
    border-radius: var(--radius);
    border: 1px solid var(--gray-200);
    overflow: hidden;
}

.calendar-day-header {
    padding: 16px 20px;
    background: var(--gray-50);
    border-bottom: 1px solid var(--gray-200);
    text-align: center;
}

.calendar-day-header .day-name {
    font-size: 14px;
    color: var(--gray-700);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.calendar-day-header .day-number {
    font-size: 32px;
    font-weight: 700;
    color: var(--gray-800);
}

.calendar-day-header.today .day-number {
    color: var(--primary);
}

.calendar-hours {
    position: relative;
}

.calendar-hour {
    display: flex;
    min-height: 60px;
    border-bottom: 1px solid var(--gray-100);
}

.calendar-hour:last-child {
    border-bottom: none;
}

.calendar-hour-label {
    width: 60px;
    padding: 8px 12px;
    font-size: 12px;
    color: var(--gray-700);
    text-align: right;
    flex-shrink: 0;
    border-right: 1px solid var(--gray-100);
}

.calendar-hour-content {
    flex: 1;
    padding: 4px 8px;
    position: relative;
}

/* Calendar Week View */
.calendar-week-view {
    background: white;
    border-radius: var(--radius);
    border: 1px solid var(--gray-200);
    overflow: hidden;
}

.calendar-week-header {
    display: grid;
    grid-template-columns: 60px repeat(7, 1fr);
    border-bottom: 1px solid var(--gray-200);
}

.calendar-week-header-cell {
    padding: 12px 8px;
    text-align: center;
    border-right: 1px solid var(--gray-100);
}

.calendar-week-header-cell:last-child {
    border-right: none;
}

.calendar-week-header-cell .day-name {
    font-size: 12px;
    color: var(--gray-700);
    text-transform: uppercase;
}

.calendar-week-header-cell .day-number {
    font-size: 18px;
    font-weight: 600;
    color: var(--gray-800);
}

.calendar-week-header-cell.today .day-number {
    background: var(--primary);
    color: white;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.calendar-week-grid {
    display: grid;
    grid-template-columns: 60px repeat(7, 1fr);
    max-height: 500px;
    overflow-y: auto;
}

.calendar-week-time {
    padding: 8px 12px;
    font-size: 12px;
    color: var(--gray-700);
    text-align: right;
    border-right: 1px solid var(--gray-100);
    border-bottom: 1px solid var(--gray-100);
}

.calendar-week-cell {
    min-height: 60px;
    border-right: 1px solid var(--gray-100);
    border-bottom: 1px solid var(--gray-100);
    padding: 2px;
}

.calendar-week-cell:last-child {
    border-right: none;
}

/* Calendar Month View */
.calendar-month-view {
    background: white;
    border-radius: var(--radius);
    border: 1px solid var(--gray-200);
    overflow: hidden;
}

.calendar-month-header {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    background: var(--gray-50);
    border-bottom: 1px solid var(--gray-200);
}

.calendar-month-header-cell {
    padding: 12px 8px;
    text-align: center;
    font-size: 12px;
    font-weight: 500;
    color: var(--gray-800);
    text-transform: uppercase;
}

.calendar-month-grid {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
}

.calendar-month-cell {
    min-height: 100px;
    border-right: 1px solid var(--gray-100);
    border-bottom: 1px solid var(--gray-100);
    padding: 8px;
}

.calendar-month-cell:nth-child(7n) {
    border-right: none;
}

.calendar-month-cell.other-month {
    background: var(--gray-50);
}

.calendar-month-cell.other-month .cell-date {
    color: var(--gray-500);
}

.calendar-month-cell .cell-date {
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-800);
    margin-bottom: 4px;
}

.calendar-month-cell.today .cell-date {
    background: var(--primary);
    color: white;
    width: 26px;
    height: 26px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* Calendar Quarter View (3 Month) */
.calendar-quarter-view {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
}

.calendar-mini-month {
    background: white;
    border-radius: var(--radius);
    border: 1px solid var(--gray-200);
    overflow: hidden;
}

.calendar-mini-month-header {
    padding: 12px;
    text-align: center;
    font-weight: 600;
    color: var(--gray-800);
    background: var(--gray-50);
    border-bottom: 1px solid var(--gray-200);
}

.calendar-mini-month-days {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    padding: 8px;
    gap: 2px;
}

.calendar-mini-day-header {
    text-align: center;
    font-size: 10px;
    color: var(--gray-700);
    padding: 4px;
}

.calendar-mini-day {
    text-align: center;
    font-size: 12px;
    padding: 4px;
    border-radius: 4px;
    color: var(--gray-800);
}

.calendar-mini-day.other-month {
    color: var(--gray-500);
}

.calendar-mini-day.today {
    background: var(--primary);
    color: white;
    font-weight: 600;
}

.calendar-mini-day.has-event {
    background: var(--primary-light);
    font-weight: 500;
}

/* Calendar Event */
.calendar-event {
    background: var(--primary-light);
    border-left: 3px solid var(--primary);
    padding: 4px 8px;
    margin-bottom: 2px;
    border-radius: 0 4px 4px 0;
    font-size: 12px;
    color: var(--gray-800);
    cursor: pointer;
    transition: all 0.15s;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.calendar-event:hover {
    background: var(--primary);
    color: white;
}

.calendar-event.completed {
    background: #D1FAE5;
    border-color: #10B981;
    opacity: 0.7;
}

.calendar-event.overdue {
    background: #FEE2E2;
    border-color: #EF4444;
}

/* Calendar Event Colors */
.calendar-event.color-blue {
    background: #DBEAFE;
    border-color: #3B82F6;
}
.calendar-event.color-blue:hover {
    background: #3B82F6;
}

.calendar-event.color-green {
    background: #D1FAE5;
    border-color: #10B981;
}
.calendar-event.color-green:hover {
    background: #10B981;
}

.calendar-event.color-purple {
    background: #EDE9FE;
    border-color: #8B5CF6;
}
.calendar-event.color-purple:hover {
    background: #8B5CF6;
}

.calendar-event.color-orange {
    background: #FEF3C7;
    border-color: #F59E0B;
}
.calendar-event.color-orange:hover {
    background: #F59E0B;
}

.calendar-event.color-red {
    background: #FEE2E2;
    border-color: #EF4444;
}
.calendar-event.color-red:hover {
    background: #EF4444;
}

/* Events in week/month cells (smaller version) */
.calendar-week-cell .calendar-event,
.calendar-month-cell .calendar-event {
    font-size: 11px;
    padding: 2px 4px;
    margin-bottom: 2px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.calendar-week-cell .calendar-event {
    font-size: 10px;
    padding: 1px 3px;
}

/* More events indicator in month view */
.more-events {
    font-size: 10px;
    color: var(--gray-600);
    padding: 2px 4px;
    cursor: pointer;
}

.more-events:hover {
    color: var(--primary);
}

/* Green highlight for days with events in quarter view */
.calendar-mini-day.has-event:not(.today) {
    background: #D1FAE5;
    color: var(--gray-800);
}

/* Hour slot clickable */
.calendar-hour-content {
    cursor: pointer;
}

.calendar-hour-content:hover {
    background: var(--primary-light);
}

/* Clickable days in week/month/quarter views */
.clickable-day {
    cursor: pointer;
    transition: background 0.15s;
}

.calendar-week-header-cell.clickable-day:hover {
    background: var(--primary-light);
}

.calendar-month-cell.clickable-day:hover {
    background: var(--primary-light);
}

.calendar-mini-day.clickable-day:hover {
    background: var(--primary-light);
}

/* Event Modal */
.modal {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    z-index: 1000;
}

.event-modal-content {
    width: 100%;
    max-width: 480px;
    background: white;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    max-height: 90vh;
    overflow-y: auto;
}

.event-modal-content .modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 20px;
    border-bottom: 1px solid var(--gray-200);
}

.event-modal-content .modal-header h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--gray-800);
    margin: 0;
}

.event-modal-content form {
    padding: 20px;
}

.color-options {
    display: flex;
    gap: 12px;
}

.color-option {
    cursor: pointer;
}

.color-option input {
    display: none;
}

.color-swatch {
    display: block;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    border: 3px solid transparent;
    transition: all 0.15s;
}

.color-option input:checked + .color-swatch {
    border-color: var(--gray-800);
    transform: scale(1.1);
}

.color-option:hover .color-swatch {
    transform: scale(1.1);
}

.modal-actions {
    display: flex;
    gap: 12px;
    justify-content: flex-end;
    margin-top: 24px;
    padding-top: 16px;
    border-top: 1px solid var(--gray-200);
}

.btn-danger {
    background: #EF4444;
    color: white;
    border: none;
}

.btn-danger:hover {
    background: #DC2626;
}

/* ============================================================
   Contacts Screen Layout
   ============================================================ */
.contacts-layout {
    display: flex;
    flex: 1;
    overflow: hidden;
}

.contacts-left {
    width: 35%;
    min-width: 280px;
    max-width: 50%;
    display: flex;
    flex-direction: column;
    background: white;
    border-right: 1px solid var(--gray-200);
}

.contacts-resizer {
    width: 6px;
    background: var(--gray-100);
    cursor: col-resize;
    transition: background 0.15s;
    flex-shrink: 0;
}

.contacts-resizer:hover,
.contacts-resizer.dragging {
    background: var(--primary);
}

.contacts-right {
    flex: 1;
    min-width: 400px;
    display: flex;
    flex-direction: column;
    background: var(--gray-50);
    overflow: hidden;
}

/* Contacts Panel */
.contacts-panel {
    display: flex;
    flex-direction: column;
    height: 100%;
}

.contacts-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 20px;
    border-bottom: 1px solid var(--gray-200);
    background: white;
}

.contacts-header h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--gray-800);
    margin: 0;
}

.contacts-search {
    padding: 12px 20px;
    border-bottom: 1px solid var(--gray-100);
}

.contacts-search input {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    background: var(--gray-50);
    font-size: 14px;
    color: var(--gray-800);
}

.contacts-search input:focus {
    outline: none;
    border-color: var(--primary);
    background: white;
}

.contacts-tabs {
    display: flex;
    padding: 0 20px;
    border-bottom: 1px solid var(--gray-200);
    background: white;
}

.contact-tab {
    padding: 12px 16px;
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-600);
    background: transparent;
    border: none;
    border-bottom: 2px solid transparent;
    cursor: pointer;
    transition: all 0.15s;
}

.contact-tab:hover {
    color: var(--gray-800);
}

.contact-tab.active {
    color: var(--primary);
    border-bottom-color: var(--primary);
}

.conversations-list {
    flex: 1;
    overflow-y: auto;
    padding: 8px;
}

.conversations-list .empty-state {
    text-align: center;
    padding: 40px 20px;
    color: var(--gray-700);
}

.conversations-list .text-muted {
    font-size: 13px;
    color: var(--gray-600);
}

/* Conversation Item */
.conversation-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    border-radius: var(--radius);
    cursor: pointer;
    transition: all 0.15s;
}

.conversation-item:hover {
    background: var(--gray-50);
}

.conversation-item.active {
    background: var(--primary-light);
}

.conversation-item.unread {
    background: var(--gray-50);
}

.conversation-avatar {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--primary);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 16px;
    flex-shrink: 0;
}

.conversation-avatar.teacher {
    background: #8B5CF6;
}

.conversation-avatar.student {
    background: #10B981;
}

.conversation-info {
    flex: 1;
    min-width: 0;
}

.conversation-name {
    font-weight: 500;
    color: var(--gray-800);
    margin-bottom: 2px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.conversation-name .time {
    font-size: 12px;
    font-weight: 400;
    color: var(--gray-500);
}

.conversation-preview {
    font-size: 13px;
    color: var(--gray-600);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.conversation-item.unread .conversation-name {
    font-weight: 600;
}

.conversation-item.unread .conversation-preview {
    color: var(--gray-800);
    font-weight: 500;
}

.unread-badge {
    width: 10px;
    height: 10px;
    background: var(--primary);
    border-radius: 50%;
    flex-shrink: 0;
}

/* ============================================================
   Math Screen
   ============================================================ */
.math-layout {
    display: flex;
    flex: 1;
    overflow: hidden;
}

.math-left {
    width: 35%;
    min-width: 240px;
    max-width: 50%;
    display: flex;
    flex-direction: column;
    background: white;
    border-right: 1px solid var(--gray-200);
    transition: width 0.25s ease, min-width 0.25s ease;
}

.math-left.collapsed {
    width: 48px;
    min-width: 48px;
}

.math-left.collapsed .math-nav-header h3,
.math-left.collapsed .math-nav-content {
    display: none;
}

.math-left.collapsed .math-nav-header {
    padding: 12px;
    justify-content: center;
}

.math-left.collapsed .math-collapse-btn .collapse-icon {
    transform: rotate(180deg);
}

.math-resizer {
    width: 6px;
    background: var(--gray-100);
    cursor: col-resize;
    transition: background 0.15s;
    flex-shrink: 0;
}

.math-resizer:hover,
.math-resizer.dragging {
    background: var(--primary);
}

.math-left.collapsed + .math-resizer {
    display: none;
}

.math-right {
    flex: 1;
    min-width: 350px;
    display: flex;
    flex-direction: column;
    background: var(--gray-50);
    overflow: hidden;
}

/* Math Navigation */
.math-nav-header {
    padding: 12px 16px;
    border-bottom: 1px solid var(--gray-200);
    background: white;
    display: flex;
    align-items: center;
    gap: 12px;
}

.math-nav-header h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--gray-800);
    margin: 0;
    flex: 1;
}

.math-collapse-btn {
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 2px solid var(--primary);
    border-radius: 6px;
    background: var(--primary);
    cursor: pointer;
    color: white;
    transition: all 0.15s;
    flex-shrink: 0;
}

.math-collapse-btn:hover {
    background: var(--primary-dark, #1d4ed8);
    border-color: var(--primary-dark, #1d4ed8);
    transform: scale(1.05);
}

.collapse-icon {
    font-size: 14px;
    font-weight: bold;
    transition: transform 0.25s ease;
}

.math-nav-content {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
}

/* Math Source Toggle (Illustrative Math / MIT) */
.math-source-toggle {
    display: flex;
    gap: 16px;
    margin-bottom: 16px;
    padding: 12px;
    background: var(--gray-50);
    border-radius: var(--radius);
    border: 1px solid var(--gray-200);
}

.math-source-toggle .math-radio-label {
    display: flex !important;
    align-items: center;
    gap: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-700);
    margin-bottom: 0 !important;
}

.math-source-toggle .math-radio-label input[type="radio"] {
    width: 16px;
    height: 16px;
    cursor: pointer;
    accent-color: var(--primary);
    display: inline-block !important;
}

.math-source-toggle .math-radio-label:hover {
    color: var(--primary);
}

/* Illustrative Math Section */
.math-illustrative-section {
    display: block;
}

/* MIT Math Section */
.math-mit-section {
    display: block;
}

.math-mit-course-selector {
    margin-bottom: 16px;
}

.math-mit-course-selector label {
    display: block;
    font-size: 13px;
    font-weight: 500;
    color: var(--gray-600);
    margin-bottom: 6px;
}

.math-mit-course-selector select {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    background: white;
    font-size: 14px;
    color: var(--gray-800);
    cursor: pointer;
}

.math-mit-course-selector select:focus {
    outline: none;
    border-color: var(--primary);
}

.math-mit-chapter-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.math-mit-chapter-item {
    display: flex;
    gap: 8px;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    background: white;
    padding: 10px 12px;
    cursor: pointer;
    transition: all 0.15s;
}

.math-mit-chapter-item:hover {
    background: var(--gray-50);
    border-color: var(--primary);
}

.math-mit-chapter-item.active {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
}

.math-mit-chapter-number {
    font-weight: 600;
    font-size: 13px;
    min-width: 24px;
}

.math-mit-chapter-title {
    font-size: 13px;
    flex: 1;
}

.math-mit-chapter-item.active .math-mit-chapter-number,
.math-mit-chapter-item.active .math-mit-chapter-title {
    color: white;
}

.math-grade-selector {
    margin-bottom: 16px;
}

.math-grade-selector label {
    display: block;
    font-size: 13px;
    font-weight: 500;
    color: var(--gray-600);
    margin-bottom: 6px;
}

.math-grade-selector select {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    background: white;
    font-size: 14px;
    color: var(--gray-800);
    cursor: pointer;
}

.math-grade-selector select:focus {
    outline: none;
    border-color: var(--primary);
}

.math-unit-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.math-unit-item {
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    background: white;
    overflow: hidden;
}

.math-unit-header {
    display: flex;
    align-items: center;
    padding: 12px 14px;
    cursor: pointer;
    transition: background 0.15s;
}

.math-unit-header:hover {
    background: var(--gray-50);
}

.math-unit-header.expanded {
    border-bottom: 1px solid var(--gray-200);
    background: var(--gray-50);
}

.math-unit-toggle {
    width: 20px;
    height: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-right: 10px;
    color: var(--gray-500);
    transition: transform 0.2s;
}

.math-unit-header.expanded .math-unit-toggle {
    transform: rotate(90deg);
}

.math-unit-title {
    flex: 1;
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-800);
}

.math-unit-number {
    font-size: 12px;
    color: var(--gray-500);
    margin-right: 8px;
}

.math-lesson-list {
    display: none;
    padding: 8px;
    background: var(--gray-50);
}

.math-unit-item.expanded .math-lesson-list {
    display: block;
}

.math-lesson-item {
    padding: 10px 12px;
    font-size: 13px;
    color: var(--gray-700);
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.15s;
}

.math-lesson-item:hover {
    background: white;
    color: var(--primary);
}

.math-lesson-item.active {
    background: var(--primary);
    color: white;
}

/* Math Lesson Display */
.math-lesson-placeholder {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.placeholder-content {
    text-align: center;
    color: var(--gray-500);
}

.placeholder-content p {
    margin-top: 16px;
    font-size: 15px;
}

.math-lesson-frame {
    flex: 1;
    width: 100%;
    border: none;
}

/* ============================================================
   ELA/Literacy Screen
   ============================================================ */
.ela-layout {
    display: flex;
    flex: 1;
    overflow: hidden;
}

.ela-left {
    width: 250px;
    min-width: 200px;
    max-width: 350px;
    display: flex;
    flex-direction: column;
    background: white;
    border-right: 1px solid var(--gray-200);
    transition: width 0.25s ease, min-width 0.25s ease;
}

.ela-left.collapsed {
    width: 48px;
    min-width: 48px;
}

.ela-left.collapsed .ela-nav-header h3,
.ela-left.collapsed .ela-nav-content {
    display: none;
}

.ela-left.collapsed .ela-nav-header {
    padding: 12px;
    justify-content: center;
}

.ela-left.collapsed .ela-collapse-btn .collapse-icon {
    transform: rotate(180deg);
}

.ela-resizer {
    width: 6px;
    background: var(--gray-100);
    cursor: col-resize;
    transition: background 0.15s;
    flex-shrink: 0;
}

.ela-resizer:hover,
.ela-resizer.dragging {
    background: var(--primary);
}

.ela-left.collapsed + .ela-resizer {
    display: none;
}

.ela-right {
    flex: 1;
    min-width: 350px;
    display: flex;
    flex-direction: column;
    background: var(--gray-50);
    overflow: hidden;
}

/* ELA Navigation */
.ela-nav-header {
    padding: 12px 16px;
    border-bottom: 1px solid var(--gray-200);
    background: white;
    display: flex;
    align-items: center;
    gap: 12px;
}

.ela-nav-header h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--gray-800);
    margin: 0;
    flex: 1;
}

.ela-collapse-btn {
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 2px solid var(--primary);
    border-radius: 6px;
    background: var(--primary);
    cursor: pointer;
    color: white;
    transition: all 0.15s;
    flex-shrink: 0;
}

.ela-collapse-btn:hover {
    background: var(--primary-dark, #1d4ed8);
    border-color: var(--primary-dark, #1d4ed8);
    transform: scale(1.05);
}

.ela-nav-content {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
}

.ela-nav-description {
    font-size: 13px;
    color: var(--gray-600);
    margin: 0 0 16px 0;
}

.ela-grade-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.ela-grade-btn {
    padding: 14px 16px;
    font-size: 15px;
    font-weight: 500;
    color: var(--gray-700);
    background: var(--gray-50);
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    cursor: pointer;
    text-align: left;
    transition: all 0.15s;
}

.ela-grade-btn:hover {
    background: white;
    border-color: var(--primary);
    color: var(--primary);
}

.ela-grade-btn.active {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
}

/* ELA Welcome Panel */
.ela-welcome-panel {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px;
    overflow-y: auto;
}

.ela-welcome-content {
    max-width: 600px;
    text-align: center;
}

.ela-odell-logo {
    max-width: 280px;
    height: auto;
    margin-bottom: 24px;
}

.ela-welcome-content h2 {
    font-size: 24px;
    font-weight: 600;
    color: var(--gray-800);
    margin: 0 0 8px 0;
}

.ela-tagline {
    font-size: 16px;
    color: var(--gray-500);
    font-style: italic;
    margin: 0 0 24px 0;
}

.ela-description {
    text-align: left;
    margin-bottom: 24px;
    padding: 20px;
    background: white;
    border-radius: var(--radius);
    border: 1px solid var(--gray-200);
}

.ela-description p {
    font-size: 14px;
    color: var(--gray-700);
    line-height: 1.6;
    margin: 0 0 12px 0;
}

.ela-description p:last-child {
    margin-bottom: 0;
}

.ela-instructions {
    text-align: left;
    margin-bottom: 24px;
    padding: 20px;
    background: white;
    border-radius: var(--radius);
    border: 1px solid var(--gray-200);
}

.ela-instructions h3 {
    font-size: 16px;
    font-weight: 600;
    color: var(--gray-800);
    margin: 0 0 12px 0;
}

.ela-instructions ol {
    margin: 0;
    padding-left: 20px;
}

.ela-instructions li {
    font-size: 14px;
    color: var(--gray-700);
    line-height: 1.6;
    margin-bottom: 8px;
}

.ela-instructions li:last-child {
    margin-bottom: 0;
}

.ela-cta {
    padding: 16px 24px;
    background: var(--primary);
    border-radius: var(--radius);
}

.ela-cta p {
    font-size: 15px;
    font-weight: 500;
    color: white;
    margin: 0;
}

/* ELA Source Toggle (Odell / MIT) */
.ela-source-toggle {
    display: flex;
    gap: 16px;
    margin-bottom: 16px;
    padding: 12px;
    background: var(--gray-50);
    border-radius: var(--radius);
    border: 1px solid var(--gray-200);
}

.ela-source-toggle .ela-radio-label {
    display: flex !important;
    align-items: center;
    gap: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-700);
    margin-bottom: 0 !important;
}

.ela-source-toggle .ela-radio-label input[type="radio"] {
    width: 16px;
    height: 16px;
    cursor: pointer;
    accent-color: var(--primary);
    display: inline-block !important;
}

.ela-source-toggle .ela-radio-label:hover {
    color: var(--primary);
}

/* ELA Odell Section */
#elaOdellSection {
    margin-top: 8px;
}

/* ELA MIT Section */
#elaMitSection {
    margin-top: 8px;
}

.ela-course-select {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    font-size: 14px;
    background: white;
    cursor: pointer;
    margin-bottom: 16px;
}

.ela-course-select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}

.ela-lesson-list {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.ela-lesson-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 14px;
    background: var(--gray-50);
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    cursor: pointer;
    transition: all 0.15s;
}

.ela-lesson-item:hover {
    background: white;
    border-color: var(--primary);
}

.ela-lesson-item.active {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
}

.ela-lesson-item .lesson-number {
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gray-200);
    border-radius: 50%;
    font-size: 12px;
    font-weight: 600;
    color: var(--gray-600);
    flex-shrink: 0;
}

.ela-lesson-item.active .lesson-number {
    background: rgba(255, 255, 255, 0.2);
    color: white;
}

.ela-lesson-item .lesson-name {
    flex: 1;
    font-size: 13px;
    font-weight: 500;
}

/* ELA MIT Placeholder */
.ela-mit-placeholder {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px;
}

.ela-mit-placeholder .placeholder-content {
    text-align: center;
}

.ela-mit-placeholder .placeholder-content p {
    font-size: 15px;
    color: var(--gray-500);
    margin: 16px 0 0 0;
}

/* ELA MIT Lesson Content */
.ela-lesson-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.ela-lesson-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 20px;
    background: white;
    border-bottom: 1px solid var(--gray-200);
}

.ela-lesson-header h2 {
    font-size: 18px;
    font-weight: 600;
    color: var(--gray-800);
    margin: 0;
}

.ela-lesson-actions {
    display: flex;
    gap: 8px;
}

.ela-iframe-container {
    flex: 1;
    display: flex;
    overflow: hidden;
}

.ela-iframe-container iframe {
    width: 100%;
    height: 100%;
    border: none;
}

/* ============================================================
   Science Screen (OpenSciEd)
   ============================================================ */
.science-layout {
    display: flex;
    flex: 1;
    overflow: hidden;
}

.science-left {
    width: 35%;
    min-width: 240px;
    max-width: 50%;
    display: flex;
    flex-direction: column;
    background: white;
    border-right: 1px solid var(--gray-200);
    transition: width 0.25s ease, min-width 0.25s ease;
}

.science-left.collapsed {
    width: 48px;
    min-width: 48px;
}

.science-left.collapsed .science-nav-header h3,
.science-left.collapsed .science-nav-content {
    display: none;
}

.science-left.collapsed .science-nav-header {
    padding: 12px;
    justify-content: center;
}

.science-left.collapsed .science-collapse-btn .collapse-icon {
    transform: rotate(180deg);
}

.science-resizer {
    width: 6px;
    background: var(--gray-100);
    cursor: col-resize;
    transition: background 0.15s;
    flex-shrink: 0;
}

.science-resizer:hover,
.science-resizer.dragging {
    background: var(--primary);
}

.science-left.collapsed + .science-resizer {
    display: none;
}

.science-right {
    flex: 1;
    min-width: 350px;
    display: flex;
    flex-direction: column;
    background: var(--gray-50);
    overflow: hidden;
}

/* Science Navigation */
.science-nav-header {
    padding: 12px 16px;
    border-bottom: 1px solid var(--gray-200);
    background: white;
    display: flex;
    align-items: center;
    gap: 12px;
}

.science-nav-header h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--gray-800);
    margin: 0;
    flex: 1;
}

.science-collapse-btn {
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 2px solid var(--primary);
    border-radius: 6px;
    background: var(--primary);
    cursor: pointer;
    color: white;
    transition: all 0.15s;
    flex-shrink: 0;
}

.science-collapse-btn:hover {
    background: var(--primary-dark, #1d4ed8);
    border-color: var(--primary-dark, #1d4ed8);
    transform: scale(1.05);
}

.science-nav-content {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
}

/* Science Source Toggle (OpenSciEd / MIT) */
.science-source-toggle {
    display: flex;
    gap: 16px;
    margin-bottom: 16px;
    padding: 12px;
    background: var(--gray-50);
    border-radius: var(--radius);
    border: 1px solid var(--gray-200);
}

.science-source-toggle .science-radio-label {
    display: flex !important;
    align-items: center;
    gap: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-700);
    margin-bottom: 0 !important;
}

.science-source-toggle .science-radio-label input[type="radio"] {
    width: 16px;
    height: 16px;
    cursor: pointer;
    accent-color: var(--primary);
    display: inline-block !important;
}

.science-source-toggle .science-radio-label:hover {
    color: var(--primary);
}

/* OpenSciEd Section */
.science-openscied-section {
    display: block;
}

/* MIT Science Section */
.science-mit-section {
    display: block;
}

.science-mit-course-selector {
    margin-bottom: 16px;
}

.science-mit-course-selector label {
    display: block;
    font-size: 13px;
    font-weight: 500;
    color: var(--gray-600);
    margin-bottom: 6px;
}

.science-mit-course-selector select {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    background: white;
    font-size: 14px;
    color: var(--gray-800);
    cursor: pointer;
}

.science-mit-course-selector select:focus {
    outline: none;
    border-color: var(--primary);
}

.science-mit-chapter-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.science-mit-chapter-item {
    display: flex;
    gap: 8px;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    background: white;
    padding: 10px 12px;
    cursor: pointer;
    transition: all 0.15s;
}

.science-mit-chapter-item:hover {
    background: var(--gray-50);
    border-color: var(--primary);
}

.science-mit-chapter-item.active {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
}

.science-mit-chapter-number {
    font-weight: 600;
    font-size: 13px;
    min-width: 24px;
}

.science-mit-chapter-title {
    font-size: 13px;
    flex: 1;
}

.science-mit-chapter-item.active .science-mit-chapter-number,
.science-mit-chapter-item.active .science-mit-chapter-title {
    color: white;
}

.science-grade-selector {
    margin-bottom: 16px;
}

.science-grade-selector label {
    display: block;
    font-size: 13px;
    font-weight: 500;
    color: var(--gray-600);
    margin-bottom: 6px;
}

.science-grade-selector select {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    background: white;
    font-size: 14px;
    color: var(--gray-800);
    cursor: pointer;
}

.science-grade-selector select:focus {
    outline: none;
    border-color: var(--primary);
}

.science-unit-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.science-unit-item {
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    background: white;
    padding: 12px 14px;
    cursor: pointer;
    transition: all 0.15s;
}

.science-unit-item:hover {
    background: var(--gray-50);
    border-color: var(--primary);
}

.science-unit-item.active {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
}

.science-unit-number {
    font-size: 12px;
    color: var(--gray-500);
    margin-bottom: 4px;
}

.science-unit-item.active .science-unit-number {
    color: rgba(255, 255, 255, 0.8);
}

.science-unit-title {
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-800);
}

.science-unit-item.active .science-unit-title {
    color: white;
}

/* Science Lesson Display */
.science-lesson-placeholder {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.science-lesson-frame {
    flex: 1;
    width: 100%;
    border: none;
}

/* Message Container */
.message-container {
    display: flex;
    flex-direction: column;
    height: 100%;
}

.message-empty-state {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 40px;
    text-align: center;
}

.empty-state-icon {
    color: var(--gray-400);
    margin-bottom: 16px;
}

.message-empty-state h3 {
    font-size: 18px;
    color: var(--gray-800);
    margin: 0 0 8px;
}

.message-empty-state p {
    color: var(--gray-600);
    margin: 0;
}

/* Message Thread */
.message-thread {
    display: flex;
    flex-direction: column;
    height: 100%;
}

.message-thread-header {
    padding: 16px 20px;
    background: white;
    border-bottom: 1px solid var(--gray-200);
}

.thread-recipient {
    display: flex;
    align-items: center;
    gap: 12px;
}

.recipient-avatar {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--primary);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 16px;
}

.recipient-avatar.teacher {
    background: #8B5CF6;
}

.recipient-avatar.student {
    background: #10B981;
}

.recipient-info h4 {
    font-size: 16px;
    font-weight: 600;
    color: var(--gray-800);
    margin: 0 0 2px;
}

.recipient-role {
    font-size: 13px;
    color: var(--gray-600);
}

.message-thread-body {
    flex: 1;
    overflow-y: auto;
    padding: 20px;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

/* Individual Message */
.message-bubble {
    max-width: 70%;
    padding: 12px 16px;
    border-radius: 16px;
    font-size: 14px;
    line-height: 1.5;
}

.message-bubble.sent {
    align-self: flex-end;
    background: var(--primary);
    color: white;
    border-bottom-right-radius: 4px;
}

.message-bubble.received {
    align-self: flex-start;
    background: white;
    color: var(--gray-800);
    border: 1px solid var(--gray-200);
    border-bottom-left-radius: 4px;
}

.message-time {
    font-size: 11px;
    margin-top: 4px;
    opacity: 0.7;
}

.message-bubble.sent .message-time {
    text-align: right;
}

/* Message Delete Button */
.message-bubble {
    position: relative;
}

.message-delete-btn {
    position: absolute;
    top: -8px;
    right: -8px;
    width: 20px;
    height: 20px;
    border-radius: 50%;
    background: var(--gray-600);
    color: white;
    border: none;
    font-size: 14px;
    line-height: 1;
    cursor: pointer;
    opacity: 0;
    transition: opacity 0.15s;
    display: flex;
    align-items: center;
    justify-content: center;
}

.message-bubble:hover .message-delete-btn {
    opacity: 1;
}

.message-delete-btn:hover {
    background: var(--danger);
}

/* Message Input Area */
.message-input-area {
    display: flex;
    gap: 12px;
    padding: 16px 20px;
    background: white;
    border-top: 1px solid var(--gray-200);
}

.message-input-area textarea {
    flex: 1;
    padding: 12px 16px;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    font-size: 14px;
    color: var(--gray-800);
    resize: none;
    min-height: 44px;
    max-height: 120px;
}

.message-input-area textarea:focus {
    outline: none;
    border-color: var(--primary);
}

.message-input-area .btn {
    align-self: flex-end;
    padding: 12px;
}

/* New Message Modal */
.new-message-modal-content {
    max-width: 500px;
}

.new-message-modal-content .modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 20px;
    border-bottom: 1px solid var(--gray-200);
}

.new-message-modal-content .modal-header h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--gray-800);
    margin: 0;
}

.new-message-modal-content form {
    padding: 20px;
}

/* Profile Modal */
.profile-modal-content {
    max-width: 360px;
    padding: 0;
}

.profile-modal-content .modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 20px;
    border-bottom: 1px solid var(--gray-200);
}

.profile-modal-content .modal-header h3 {
    font-size: 18px;
    font-weight: 600;
    color: var(--gray-800);
    margin: 0;
}

.profile-modal-body {
    padding: 0;
}

.profile-user-info {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 20px;
    background: var(--gray-50);
    border-bottom: 1px solid var(--gray-200);
}

.profile-avatar {
    width: 56px;
    height: 56px;
    border-radius: 50%;
    background: var(--primary);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
    font-weight: 600;
}

.profile-details h4 {
    font-size: 16px;
    font-weight: 600;
    color: var(--gray-800);
    margin: 0 0 4px 0;
}

.profile-email {
    font-size: 13px;
    color: var(--gray-500);
}

.profile-menu {
    padding: 8px 0;
}

.profile-menu-item {
    display: flex;
    align-items: center;
    gap: 12px;
    width: 100%;
    padding: 12px 20px;
    border: none;
    background: transparent;
    cursor: pointer;
    font-size: 14px;
    color: var(--gray-700);
    transition: background 0.15s;
    text-align: left;
}

.profile-menu-item:hover {
    background: var(--gray-100);
}

.profile-menu-item svg {
    color: var(--gray-500);
    flex-shrink: 0;
}

.profile-menu-item:hover svg {
    color: var(--gray-700);
}

.profile-menu-item.danger {
    color: var(--danger);
}

.profile-menu-item.danger svg {
    color: var(--danger);
}

.profile-menu-item.danger:hover {
    background: #FEE2E2;
}

.profile-menu-divider {
    height: 1px;
    background: var(--gray-200);
    margin: 8px 0;
}

/* ============================================================
   Auth Panel
   ============================================================ */
.auth-panel {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px 20px;
    background: white;
}

.auth-box {
    width: 100%;
    max-width: 400px;
    padding: 32px;
    background: white;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
}

.auth-greeting {
    text-align: center;
    font-size: 18px;
    color: var(--gray-700);
    margin-bottom: 8px;
    font-weight: 500;
}

.auth-box h2 {
    text-align: center;
    margin-bottom: 24px;
    font-size: 24px;
}

.auth-error {
    padding: 12px;
    margin-bottom: 16px;
    background: #fef2f2;
    border: 1px solid #fecaca;
    border-radius: var(--radius);
    color: #dc2626;
    font-size: 13px;
}

.auth-toggle {
    margin-top: 16px;
    text-align: center;
    font-size: 13px;
    color: var(--gray-500);
}

/* ============================================================
   Selector Bar - Centered
   ============================================================ */
.selector-bar {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    padding: 12px 24px;
    background: var(--gray-50);
    border-bottom: 1px solid var(--gray-200);
}

.selector-bar label {
    font-weight: 500;
    color: var(--gray-700);
}

.selector-bar select {
    width: 300px;
}

/* ============================================================
   Main Content
   ============================================================ */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
}

/* ============================================================
   Panel Base
   ============================================================ */
.panel {
    flex: 1;
    padding: 24px;
}

/* ============================================================
   Welcome Panel
   ============================================================ */
.welcome-panel {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
}

.welcome-panel h2 {
    font-size: 28px;
    color: var(--gray-800);
    margin-bottom: 12px;
}

.welcome-panel p {
    color: var(--gray-500);
    max-width: 400px;
}

/* ============================================================
   Create Panel
   ============================================================ */
.create-panel {
    max-width: 500px;
    margin: 0 auto;
    background: white;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow);
    padding: 32px;
}

.create-panel h2 {
    margin-bottom: 24px;
}

/* ============================================================
   Notebook Panel (Two Column with Resize)
   ============================================================ */
.notebook-panel {
    display: flex;
    padding: 0;
    height: calc(100vh - 120px);
    overflow: hidden;
}

/* Sources Sidebar - 300px default, resizable */
.sources-sidebar {
    width: var(--sources-width);
    min-width: 200px;
    max-width: 500px;
    background: white;
    border-right: 1px solid var(--gray-200);
    display: flex;
    flex-direction: column;
    overflow: hidden;
    flex-shrink: 0;
    position: relative;
    transition: width 0.2s ease, min-width 0.2s ease;
}

.sources-sidebar.collapsed {
    width: 48px !important;
    min-width: 48px !important;
}

.sources-sidebar.collapsed .sources-sidebar-content {
    display: none;
}

.sidebar-collapse-btn {
    position: absolute;
    top: 8px;
    right: 8px;
    width: 28px;
    height: 28px;
    border: 1px solid var(--gray-300);
    background: white;
    border-radius: 4px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--gray-500);
    transition: all 0.15s;
    z-index: 10;
    font-size: 12px;
}

.sidebar-collapse-btn:hover {
    background: var(--gray-100);
    color: var(--gray-700);
}

.sources-sidebar.collapsed .sidebar-collapse-btn {
    right: 50%;
    transform: translateX(50%);
    top: 12px;
}

.sources-sidebar.collapsed .sidebar-collapse-btn .collapse-icon {
    transform: rotate(180deg);
}

.sources-sidebar-content {
    display: flex;
    flex-direction: column;
    flex: 1;
    overflow: hidden;
}

/* Resize Handle */
.resize-handle {
    width: 6px;
    background: var(--gray-200);
    cursor: col-resize;
    flex-shrink: 0;
    transition: background 0.15s;
}

.resize-handle:hover,
.resize-handle.dragging {
    background: var(--primary);
}

.sources-header {
    display: none;
}

.sources-header h3 {
    font-size: 16px;
    font-weight: 600;
    color: var(--gray-700);
}

/* Source Display (single source) */
.source-display {
    padding: 16px;
    border-bottom: 1px solid var(--gray-200);
}

.source-display .source-label {
    font-size: 16px;
    font-weight: 600;
    color: var(--gray-700);
    margin: 0;
    line-height: 1.5;
}

.source-display .source-title {
    font-size: 14px;
    font-weight: 400;
    color: var(--gray-600);
    margin: 0;
    line-height: 1.5;
    word-break: break-word;
}

.source-display .empty-message {
    font-size: 14px;
    color: var(--gray-400);
    margin: 0;
    line-height: 1.5;
}

.source-display .btn-full {
    margin-top: 12px;
}

.source-display .source-card {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 12px;
    background: var(--gray-50);
    border-radius: var(--radius);
    margin-bottom: 12px;
}

.source-display .source-card .source-title {
    flex: 1;
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-800);
    word-break: break-word;
}

.source-display .source-card .source-delete {
    background: none;
    border: none;
    color: var(--gray-400);
    cursor: pointer;
    font-size: 18px;
    padding: 4px 8px;
    opacity: 0;
    transition: opacity 0.15s, color 0.15s;
}

.source-display .source-card:hover .source-delete {
    opacity: 1;
}

.source-display .source-card .source-delete:hover {
    color: var(--danger);
}

.btn-full {
    width: 100%;
    justify-content: center;
}

/* Tool Buttons in sidebar */
.tool-buttons {
    display: flex;
    flex-direction: column;
    padding: 0;
    overflow-y: auto;
    flex: 1;
}

.btn-tool-full {
    display: flex;
    align-items: center;
    justify-content: flex-start;
    gap: 10px;
    width: 100%;
    padding: 12px 16px;
    background: transparent;
    border: none;
    border-bottom: 1px solid var(--gray-200);
    border-radius: 0;
    color: var(--gray-700);
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.15s;
    text-align: left;
}

.btn-tool-full:last-child {
    border-bottom: none;
}

.btn-tool-full:hover {
    background: var(--gray-100);
}

.btn-tool-full svg {
    flex-shrink: 0;
    color: var(--gray-500);
}

.btn-tool-full:hover svg {
    color: var(--primary);
}

/* Legacy source list styles (for backwards compatibility) */
.sources-list {
    flex: 1;
    overflow-y: auto;
    padding: 12px;
}

.empty-message {
    text-align: center;
    padding: 20px;
    color: var(--gray-400);
    font-size: 13px;
}

/* Source Items (legacy) */
.source-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 12px;
    background: var(--gray-50);
    border-radius: var(--radius);
    margin-bottom: 8px;
    transition: all 0.15s;
}
.source-item:hover { background: var(--gray-100); }
.source-item.disabled { opacity: 0.5; }

.source-toggle {
    position: relative;
    width: 36px;
    height: 20px;
    flex-shrink: 0;
}

.source-toggle input {
    opacity: 0;
    width: 0;
    height: 0;
    position: absolute;
}

.toggle-slider {
    position: absolute;
    inset: 0;
    background: var(--gray-300);
    border-radius: 20px;
    cursor: pointer;
    transition: background 0.2s;
}

.toggle-slider::before {
    content: '';
    position: absolute;
    top: 2px;
    left: 2px;
    width: 16px;
    height: 16px;
    background: white;
    border-radius: 50%;
    transition: transform 0.2s;
}

.source-toggle input:checked + .toggle-slider {
    background: var(--success);
}

.source-toggle input:checked + .toggle-slider::before {
    transform: translateX(16px);
}

.source-info {
    flex: 1;
    min-width: 0;
}

.source-title {
    display: block;
    font-size: 13px;
    font-weight: 500;
    color: var(--gray-800);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.source-meta {
    font-size: 12px;
    color: var(--gray-500);
}

.source-delete {
    opacity: 0;
    background: none;
    border: none;
    color: var(--gray-400);
    cursor: pointer;
    font-size: 18px;
    padding: 4px;
    transition: opacity 0.15s;
}
.source-item:hover .source-delete { opacity: 1; }
.source-delete:hover { color: var(--danger); }

/* Chat Area - Takes remaining space */
.chat-area {
    flex: 1;
    display: flex;
    flex-direction: column;
    background: var(--gray-50);
    overflow: hidden;
    min-width: 0;
}

.notebook-header {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 12px 24px;
    background: white;
    border-bottom: 1px solid var(--gray-200);
}

.notebook-header-tools {
    display: flex;
    align-items: center;
    gap: 8px;
    flex-wrap: wrap;
    justify-content: center;
}

.btn-tool {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 14px;
    font-size: 13px;
}

.btn-tool svg {
    flex-shrink: 0;
}

.subject-badge {
    display: inline-block;
    padding: 2px 8px;
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    border-radius: 4px;
    background: var(--primary-light);
    color: var(--primary);
}

.chat-container {
    flex: 1;
    overflow-y: auto;
    padding: 24px;
}

.chat-welcome {
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--gray-400);
    text-align: center;
}

.chat-message {
    max-width: 85%;
    margin-bottom: 16px;
    padding: 12px 16px;
    border-radius: var(--radius-lg);
    line-height: 1.6;
}

.chat-message-user {
    margin-left: auto;
    background: var(--primary);
    color: white;
    border-bottom-right-radius: 4px;
}

.chat-message-ai {
    background: white;
    border: 1px solid var(--gray-200);
    border-bottom-left-radius: 4px;
}

.chat-message.loading {
    color: var(--gray-500);
    font-style: italic;
}

.chat-input-area {
    display: flex;
    gap: 12px;
    padding: 16px 24px;
    background: white;
    border-top: 1px solid var(--gray-200);
}

.chat-input-area input {
    flex: 1;
}

/* Sources List at End of Message (no inline footnotes) */
.sources-used {
    margin-top: 16px;
    padding-top: 12px;
    border-top: 1px solid var(--gray-200);
    font-size: 12px;
    color: var(--gray-500);
}

.sources-used-title {
    font-weight: 600;
    color: var(--gray-600);
    margin-bottom: 6px;
}

.sources-used ul {
    margin: 0;
    padding-left: 16px;
}

.sources-used li {
    margin-bottom: 2px;
}

/* ============================================================
   Tools Panel - Right side icons
   ============================================================ */
.tools-panel {
    width: 60px;
    background: var(--gray-50);
    border-left: 1px solid var(--gray-200);
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 16px 0;
    gap: 8px;
    flex-shrink: 0;
}

.tool-btn {
    width: 44px;
    height: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    cursor: pointer;
    transition: all 0.15s;
    color: var(--gray-500);
}

.tool-btn:hover {
    background: var(--primary-light);
    border-color: var(--primary);
    color: var(--primary);
}

.tool-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.tool-btn svg {
    width: 20px;
    height: 20px;
}

.tool-btn[title]::after {
    content: attr(title);
}

/* ============================================================
   Modal Size Variants
   ============================================================ */
.modal-content.modal-lg {
    max-width: 800px;
    width: 90%;
}

.modal-content.modal-lg .modal-body {
    min-height: 400px;
}

.modal-content.modal-xl {
    max-width: 1100px;
    width: 95%;
}

.modal-content.modal-xl .modal-body {
    min-height: 500px;
}

/* ============================================================
   Reader Modal Styles
   ============================================================ */
.reader-modal {
    max-width: 1200px;
    width: 95%;
    height: 85vh;
    display: flex;
    flex-direction: column;
}

.reader-body {
    flex: 1;
    overflow: hidden;
    padding: 0 !important;
}

.reader-layout {
    display: flex;
    height: 100%;
}

.reader-sidebar {
    width: 200px;
    min-width: 200px;
    border-right: 1px solid var(--gray-200);
    display: flex;
    flex-direction: column;
    background: var(--gray-50);
}

.reader-sidebar h4 {
    padding: 16px;
    margin: 0;
    font-size: 14px;
    font-weight: 600;
    color: var(--gray-700);
    border-bottom: 1px solid var(--gray-200);
}

.reader-sources-list {
    flex: 1;
    overflow-y: auto;
    padding: 8px;
}

.reader-source-item {
    padding: 10px 12px;
    border-radius: var(--radius);
    cursor: pointer;
    font-size: 13px;
    color: var(--gray-700);
    margin-bottom: 4px;
    transition: all 0.15s;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.reader-source-item:hover {
    background: var(--gray-200);
}

.reader-source-item.active {
    background: var(--primary);
    color: white;
}

.reader-content-area {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.reader-content {
    flex: 1;
    overflow-y: auto;
    padding: 24px;
    line-height: 1.7;
    font-size: 15px;
    color: var(--gray-800);
}

.reader-content p {
    margin-bottom: 1em;
}

.reader-empty-state {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 100%;
    color: var(--gray-500);
}

.reader-notes-panel {
    width: 280px;
    min-width: 280px;
    border-left: 1px solid var(--gray-200);
    display: flex;
    flex-direction: column;
    background: var(--gray-50);
}

.reader-notes-header {
    padding: 12px 16px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    border-bottom: 1px solid var(--gray-200);
}

.reader-notes-header h4 {
    margin: 0;
    font-size: 14px;
    font-weight: 600;
    color: var(--gray-700);
}

.reader-notes-textarea {
    flex: 1;
    border: none;
    padding: 16px;
    font-size: 14px;
    line-height: 1.6;
    resize: none;
    background: transparent;
    color: var(--gray-800);
}

.reader-notes-textarea:focus {
    outline: none;
}

.reader-notes-textarea::placeholder {
    color: var(--gray-400);
}

/* Reader Toolbar */
.reader-toolbar {
    display: flex;
    gap: 8px;
    align-items: center;
    padding: 8px 12px;
    background: var(--gray-50);
    border-bottom: 1px solid var(--gray-200);
    border-radius: var(--radius) var(--radius) 0 0;
}

.btn-highlight {
    background: #fef08a;
    color: var(--gray-800);
    border: 1px solid #fde047;
}

.btn-highlight:hover {
    background: #fde047;
}

.highlight-status {
    font-size: 12px;
    color: var(--gray-500);
    margin-left: 8px;
}

/* Highlights in content */
.reader-content .highlight {
    background: #fef08a;
    padding: 1px 2px;
    border-radius: 2px;
    cursor: pointer;
    transition: background 0.2s;
}

.reader-content .highlight:hover {
    background: #fde047;
}

.reader-content .highlight.highlight-flash {
    animation: highlightFlash 0.5s ease-in-out 2;
}

@keyframes highlightFlash {
    0%, 100% { background: #fef08a; }
    50% { background: #fbbf24; }
}

/* Highlights section in notes panel */
.reader-highlights-section {
    margin-top: 16px;
    padding-top: 16px;
    padding-left: 8px;
    border-top: 1px solid var(--gray-200);
}

/* ============================================================
   Inline Reader View (replaces chat when reading)
   ============================================================ */
#readerView {
    display: flex;
    flex-direction: column;
    height: calc(100vh - 180px);
    max-height: calc(100vh - 180px);
    overflow: hidden;
}

.reader-search-bar {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 12px;
    background: var(--gray-100);
    border-bottom: 1px solid var(--gray-200);
    flex-shrink: 0;
}

.reader-search-bar input {
    flex: 1;
    max-width: 300px;
    padding: 6px 10px;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius-sm);
    font-size: 14px;
}

.reader-search-bar input:focus {
    outline: none;
    border-color: var(--primary);
}

#readerSearchResults {
    font-size: 13px;
    color: var(--gray-600);
    min-width: 60px;
}

.btn-note {
    background: #bfdbfe;
    color: var(--gray-800);
    border: 1px solid #93c5fd;
}

.btn-note:hover {
    background: #93c5fd;
}

.reader-inline-layout {
    display: flex;
    flex: 1;
    overflow: hidden;
    min-height: 0;
}

.reader-inline-content {
    flex: 1;
    padding: 16px;
    overflow-y: auto;
    background: white;
    line-height: 1.7;
    font-size: 15px;
    min-height: 0;
}

.reader-question-bar {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px;
    background: var(--gray-50);
    border-top: 1px solid var(--gray-200);
    flex-shrink: 0;
}

.reader-question-bar input {
    flex: 1;
    padding: 10px 14px;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius-md);
    font-size: 14px;
}

.reader-question-bar input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.1);
}

.reader-inline-content .search-match {
    background: #fed7aa;
    padding: 1px 0;
}

.reader-inline-content .search-match.current {
    background: #fb923c;
}

.reader-inline-content p {
    margin: 0 0 16px 0;
}

.reader-inline-content .highlight {
    background: #fef08a;
    padding: 1px 2px;
    border-radius: 2px;
    cursor: pointer;
}

.reader-inline-content .highlight:hover {
    background: #fde047;
}

.reader-inline-content .source-note {
    background: #bfdbfe;
    padding: 1px 2px;
    border-radius: 2px;
    cursor: pointer;
    border-bottom: 2px solid #3b82f6;
}

.reader-inline-content .source-note:hover {
    background: #93c5fd;
}

.reader-inline-annotations {
    width: 280px;
    border-left: 1px solid var(--gray-200);
    background: var(--gray-50);
    overflow-y: auto;
    flex-shrink: 0;
}

.annotations-toolbar {
    padding: 8px 12px;
    border-bottom: 1px solid var(--gray-200);
    display: flex;
    gap: 8px;
    align-items: center;
}

.annotations-section {
    padding: 12px;
    border-bottom: 1px solid var(--gray-200);
}

.annotations-section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 8px;
}

.annotations-section-header h4 {
    font-size: 13px;
    font-weight: 600;
    color: var(--gray-700);
    margin: 0;
    padding-left: 4px;
}

.annotations-section h4 {
    font-size: 13px;
    font-weight: 600;
    color: var(--gray-700);
    margin: 0 0 8px 0;
    padding-left: 4px;
}

.annotations-list {
    padding-left: 4px;
}

.annotations-list .text-muted {
    font-size: 12px;
    padding-left: 4px;
}

.reader-highlights-section h4 {
    font-size: 13px;
    font-weight: 600;
    color: var(--gray-700);
    margin: 0 0 8px 0;
}

.highlights-list {
    max-height: 200px;
    overflow-y: auto;
    padding-left: 4px;
}

.highlight-item {
    position: relative;
    padding: 8px 24px 8px 8px;
    margin-bottom: 6px;
    background: #fefce8;
    border: 1px solid #fef08a;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: background 0.2s;
}

.highlight-item:hover {
    background: #fef9c3;
}

.highlight-preview {
    font-size: 12px;
    color: var(--gray-700);
    font-style: italic;
    line-height: 1.4;
}

.highlight-note {
    font-size: 11px;
    color: var(--gray-500);
    margin-top: 4px;
    padding-top: 4px;
    border-top: 1px dashed var(--gray-300);
}

.btn-delete-highlight {
    position: absolute;
    top: 4px;
    right: 4px;
    width: 18px;
    height: 18px;
    padding: 0;
    border: none;
    background: transparent;
    color: var(--gray-400);
    font-size: 14px;
    cursor: pointer;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.btn-delete-highlight:hover {
    background: var(--danger);
    color: white;
}

/* Inline Reader Annotation Items */
.annotation-item {
    position: relative;
    padding: 8px 24px 8px 8px;
    margin-bottom: 6px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: background 0.2s;
}

.annotation-item.highlight-item {
    background: #fefce8;
    border: 1px solid #fef08a;
}

.annotation-item.highlight-item:hover {
    background: #fef9c3;
}

.annotation-item.note-item {
    background: #eff6ff;
    border: 1px solid #bfdbfe;
}

.annotation-item.note-item:hover {
    background: #dbeafe;
}

.annotation-preview {
    font-size: 12px;
    color: var(--gray-700);
    font-style: italic;
    line-height: 1.4;
}

.annotation-note {
    font-size: 11px;
    color: var(--gray-600);
    margin-top: 4px;
    padding-top: 4px;
    border-top: 1px dashed var(--gray-300);
    font-style: normal;
}

.btn-delete-annotation {
    position: absolute;
    top: 4px;
    right: 4px;
    width: 18px;
    height: 18px;
    padding: 0;
    border: none;
    background: transparent;
    color: var(--gray-400);
    font-size: 14px;
    cursor: pointer;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
}

.btn-delete-annotation:hover {
    background: var(--danger);
    color: white;
}

/* Highlight flash animation for scrolling to annotations */
.highlight-flash {
    animation: highlightFlash 1s ease;
}

@keyframes highlightFlash {
    0%, 100% { opacity: 1; }
    25% { opacity: 0.5; }
    50% { opacity: 1; }
    75% { opacity: 0.5; }
}

/* Source selection styling for reader mode */
.source-item.reader-selectable {
    cursor: pointer;
}

.source-item.reader-selectable:hover {
    background: var(--gray-100);
}

.source-item.reader-selected {
    background: var(--primary-light);
    border-color: var(--primary);
}

/* ============================================================
   Mind Map Styles
   ============================================================ */
.mindmap-container {
    width: 100%;
    height: 500px;
    overflow: auto;
    position: relative;
    background: linear-gradient(var(--gray-100) 1px, transparent 1px),
                linear-gradient(90deg, var(--gray-100) 1px, transparent 1px);
    background-size: 20px 20px;
    border-radius: var(--radius);
}

.mindmap-svg {
    min-width: 100%;
    min-height: 100%;
}

.mindmap-node {
    cursor: pointer;
}

.mindmap-node-rect {
    rx: 8;
    ry: 8;
    transition: all 0.2s;
}

.mindmap-node:hover .mindmap-node-rect {
    filter: brightness(0.95);
}

.mindmap-node-text {
    font-family: inherit;
    font-size: 13px;
    fill: var(--gray-800);
    pointer-events: none;
}

.mindmap-node.level-0 .mindmap-node-rect {
    fill: var(--primary);
}
.mindmap-node.level-0 .mindmap-node-text {
    fill: white;
    font-weight: 600;
    font-size: 15px;
}

.mindmap-node.level-1 .mindmap-node-rect {
    fill: var(--primary-light);
    stroke: var(--primary);
    stroke-width: 2;
}
.mindmap-node.level-1 .mindmap-node-text {
    font-weight: 500;
}

.mindmap-node.level-2 .mindmap-node-rect {
    fill: white;
    stroke: var(--gray-300);
    stroke-width: 1;
}

.mindmap-link {
    fill: none;
    stroke: var(--gray-300);
    stroke-width: 2;
}

.mindmap-link.level-0 {
    stroke: var(--primary);
    stroke-width: 3;
}

.mindmap-link.level-1 {
    stroke: var(--gray-400);
}

.mindmap-connection {
    fill: none;
    stroke: var(--warning);
    stroke-width: 1.5;
    stroke-dasharray: 5, 5;
    opacity: 0.7;
}

.mindmap-connection-label {
    font-size: 10px;
    fill: var(--gray-500);
    font-style: italic;
}

/* ============================================================
   Flashcards Modal
   ============================================================ */

.flashcard-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
}

.flashcard {
    width: 100%;
    min-height: 200px;
    perspective: 1000px;
}

.flashcard-inner {
    position: relative;
    width: 100%;
    min-height: 200px;
    transition: transform 0.6s;
    transform-style: preserve-3d;
    cursor: pointer;
}

.flashcard.flipped .flashcard-inner {
    transform: rotateY(180deg);
}

.flashcard-front,
.flashcard-back {
    position: absolute;
    width: 100%;
    min-height: 200px;
    backface-visibility: hidden;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 24px;
    border-radius: var(--radius-lg);
    text-align: center;
    font-size: 16px;
    line-height: 1.6;
}

.flashcard-front {
    background: var(--primary-light);
    color: var(--primary-hover);
    border: 2px solid var(--primary);
}

.flashcard-back {
    background: var(--gray-100);
    color: var(--gray-800);
    border: 2px solid var(--gray-300);
    transform: rotateY(180deg);
}

.flashcard-nav {
    display: flex;
    align-items: center;
    gap: 16px;
}

.flashcard-nav button {
    padding: 8px 16px;
}

.flashcard-counter {
    font-size: 14px;
    color: var(--gray-500);
}

.flashcard-hint {
    font-size: 12px;
    color: var(--gray-400);
    text-align: center;
}

/* ============================================================
   Quiz Modal
   ============================================================ */
.quiz-container {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.quiz-question {
    padding: 20px;
    background: var(--gray-50);
    border-radius: var(--radius);
    border: 1px solid var(--gray-200);
}

.quiz-question-text {
    font-size: 16px;
    font-weight: 500;
    color: var(--gray-800);
    margin-bottom: 16px;
}

.quiz-options {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.quiz-option {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    cursor: pointer;
    transition: all 0.15s;
}

.quiz-option:hover {
    border-color: var(--primary);
    background: var(--primary-light);
}

.quiz-option.selected {
    border-color: var(--primary);
    background: var(--primary-light);
}

.quiz-option.correct {
    border-color: var(--success);
    background: #d1fae5;
}

.quiz-option.incorrect {
    border-color: var(--danger);
    background: #fee2e2;
}

.quiz-option input[type="radio"] {
    width: auto;
    margin: 0;
}

.quiz-option label {
    flex: 1;
    cursor: pointer;
    margin: 0;
}

.quiz-progress {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 0;
    border-bottom: 1px solid var(--gray-200);
    margin-bottom: 12px;
}

.quiz-score {
    font-size: 14px;
    color: var(--gray-600);
}

.quiz-results {
    text-align: center;
    padding: 40px 20px;
}

.quiz-results h3 {
    font-size: 24px;
    margin-bottom: 12px;
}

.quiz-results .score-display {
    font-size: 48px;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 8px;
}

.quiz-results .score-text {
    color: var(--gray-500);
    margin-bottom: 24px;
}

.generating-indicator {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 60px 20px;
    gap: 16px;
}

.generating-indicator .spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--gray-200);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* ============================================================
   Modal
   ============================================================ */
.modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    z-index: 99999;
}

.modal-content {
    width: 100%;
    max-width: 500px;
    background: white;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    max-height: 90vh;
    display: flex;
    flex-direction: column;
}

.modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 20px;
    border-bottom: 1px solid var(--gray-200);
}

.modal-header h3 {
    font-size: 16px;
    color: var(--gray-800);
}

.modal-body {
    padding: 20px;
    overflow-y: auto;
}

.modal-footer {
    display: flex;
    justify-content: flex-end;
    gap: 8px;
    padding: 16px 20px;
    border-top: 1px solid var(--gray-200);
}

/* Source Tabs */
.source-tabs {
    display: flex;
    gap: 0;
    border-bottom: 1px solid var(--gray-200);
    margin-bottom: 20px;
}

.source-tab {
    flex: 1;
    padding: 10px 16px;
    background: none;
    border: none;
    border-bottom: 2px solid transparent;
    margin-bottom: -1px;
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-500);
    cursor: pointer;
    transition: all 0.15s;
}

.source-tab:hover { color: var(--gray-700); }
.source-tab.active {
    color: var(--primary);
    border-bottom-color: var(--primary);
}

.source-tab-content {
    display: block;
}

/* Upload Progress */
.upload-progress {
    text-align: center;
    padding: 20px;
}

.progress-bar {
    height: 6px;
    background: var(--gray-200);
    border-radius: 3px;
    overflow: hidden;
    margin-bottom: 12px;
}

.progress-fill {
    height: 100%;
    width: 30%;
    background: var(--primary);
    border-radius: 3px;
    animation: progress-indeterminate 1.5s infinite ease-in-out;
}

@keyframes progress-indeterminate {
    0% { transform: translateX(-100%); }
    100% { transform: translateX(400%); }
}

.upload-progress p {
    font-size: 13px;
    color: var(--gray-500);
    margin: 0;
}

/* ============================================================
   Responsive
   ============================================================ */
@media (max-width: 1200px) {
    .app-container {
        max-width: 100%;
        box-shadow: none;
    }
}

@media (max-width: 900px) {
    .notebook-panel {
        flex-direction: column;
        height: auto;
    }

    .sources-sidebar {
        width: 100% !important;
        max-width: 100%;
        border-right: none;
        border-bottom: 1px solid var(--gray-200);
        max-height: 250px;
    }

    .resize-handle {
        display: none;
    }

    .chat-area {
        min-height: 400px;
    }
}

@media (max-width: 600px) {
    .selector-bar {
        flex-wrap: wrap;
    }

    .selector-bar select {
        width: 100%;
    }

    .form-row {
        grid-template-columns: 1fr;
    }
}

/* ============================================================
   Podcast Player Styles
   ============================================================ */
.podcast-player {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.podcast-header {
    text-align: center;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--gray-200);
}

.podcast-header h4 {
    font-size: 20px;
    color: var(--gray-800);
    margin-bottom: 8px;
}

.podcast-description {
    font-size: 14px;
    color: var(--gray-500);
    margin: 0;
}

.podcast-controls {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
}

.podcast-btn {
    padding: 10px;
    min-width: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.podcast-btn-play {
    width: 56px;
    height: 56px;
    border-radius: 50%;
    padding: 0;
    display: flex;
    align-items: center;
    justify-content: center;
}

.podcast-btn-play svg {
    width: 28px;
    height: 28px;
}

.podcast-progress {
    text-align: center;
    font-size: 14px;
    color: var(--gray-500);
}

.podcast-current-segment {
    background: var(--gray-50);
    border-radius: var(--radius);
    padding: 20px;
    border: 1px solid var(--gray-200);
}

.podcast-current-segment h5 {
    font-size: 16px;
    color: var(--gray-800);
    margin-bottom: 12px;
}

.podcast-text {
    font-size: 14px;
    line-height: 1.7;
    color: var(--gray-700);
    margin: 0;
    max-height: 150px;
    overflow-y: auto;
}

.podcast-segments-list {
    border-top: 1px solid var(--gray-200);
    padding-top: 16px;
}

.podcast-segments-list h5 {
    font-size: 14px;
    color: var(--gray-600);
    margin-bottom: 12px;
}

.podcast-segment {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 10px 12px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: background 0.15s;
}

.podcast-segment:hover {
    background: var(--gray-100);
}

.podcast-segment.active {
    background: var(--primary-light);
}

.podcast-segment.playing .segment-number {
    background: var(--primary);
    color: white;
    animation: pulse 1.5s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.6; }
}

.segment-number {
    width: 28px;
    height: 28px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gray-200);
    color: var(--gray-600);
    font-size: 12px;
    font-weight: 600;
    border-radius: 50%;
    flex-shrink: 0;
}

.segment-title {
    font-size: 14px;
    color: var(--gray-700);
}

.cached-info {
    text-align: center;
    color: var(--gray-500);
    font-size: 12px;
    margin-bottom: 8px;
}

/* ============================================================
   Video/Slideshow Player Styles
   ============================================================ */
.video-player {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.slide-display {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-hover) 100%);
    border-radius: var(--radius-lg);
    min-height: 320px;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px;
}

.slide-content {
    text-align: center;
    color: white;
    max-width: 700px;
}

.slide-title {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 24px;
    text-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

.slide-bullets {
    list-style: none;
    padding: 0;
    margin: 0;
    text-align: left;
}

.slide-bullets li {
    font-size: 18px;
    padding: 8px 0;
    padding-left: 32px;
    position: relative;
    line-height: 1.5;
}

.slide-bullets li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 10px;
    height: 10px;
    background: rgba(255,255,255,0.8);
    border-radius: 50%;
}

.video-controls {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
}

.video-btn {
    padding: 10px;
    min-width: 44px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.video-btn-play {
    width: 56px;
    height: 56px;
    border-radius: 50%;
    padding: 0;
    display: flex;
    align-items: center;
    justify-content: center;
}

.video-btn-play svg {
    width: 28px;
    height: 28px;
}

.video-progress {
    text-align: center;
    font-size: 14px;
    color: var(--gray-500);
}

.slide-notes {
    background: var(--gray-50);
    border-radius: var(--radius);
    padding: 16px;
    font-size: 14px;
    color: var(--gray-700);
    line-height: 1.6;
    border: 1px solid var(--gray-200);
}

.slide-thumbnails {
    display: flex;
    gap: 8px;
    overflow-x: auto;
    padding: 8px 0;
    border-top: 1px solid var(--gray-200);
    padding-top: 16px;
}

.slide-thumbnail {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    padding: 8px 12px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-sm);
    cursor: pointer;
    min-width: 80px;
    transition: all 0.15s;
}

.slide-thumbnail:hover {
    border-color: var(--primary);
    background: var(--gray-50);
}

.slide-thumbnail.active {
    border-color: var(--primary);
    background: var(--primary-light);
}

.slide-number {
    font-size: 14px;
    font-weight: 600;
    color: var(--gray-600);
}

.slide-thumbnail.active .slide-number {
    color: var(--primary);
}

.slide-preview {
    font-size: 11px;
    color: var(--gray-500);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 70px;
}

/* ============================================================
   Slide Deck Styles
   ============================================================ */
.slidedeck-player {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.slidedeck-display {
    background: linear-gradient(135deg, #4F46E5 0%, #7C3AED 100%);
    border-radius: var(--radius-lg);
    min-height: 350px;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 40px;
}

.slidedeck-display.title-slide {
    min-height: 400px;
    background: linear-gradient(135deg, #1e3a8a 0%, #3730a3 100%);
}

.slidedeck-slide-content {
    text-align: center;
    color: white;
    max-width: 750px;
    width: 100%;
}

.slidedeck-title {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 24px;
    text-shadow: 0 2px 4px rgba(0,0,0,0.2);
}

.title-slide .slidedeck-title {
    font-size: 42px;
    margin-bottom: 0;
}

.slidedeck-bullets {
    list-style: none;
    padding: 0;
    margin: 0;
    text-align: left;
}

.slidedeck-bullets li {
    font-size: 18px;
    padding: 10px 0;
    padding-left: 36px;
    position: relative;
    line-height: 1.5;
}

.slidedeck-bullets li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 12px;
    height: 12px;
    background: rgba(255,255,255,0.9);
    border-radius: 50%;
}

.slidedeck-controls {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 8px 0;
}

.slidedeck-progress {
    font-size: 14px;
    color: var(--gray-500);
    font-weight: 500;
}

.slidedeck-notes {
    background: var(--gray-50);
    border-radius: var(--radius);
    padding: 16px;
    font-size: 14px;
    color: var(--gray-700);
    line-height: 1.6;
    border: 1px solid var(--gray-200);
}

.slidedeck-thumbnails {
    border-top: 1px solid var(--gray-200);
    padding-top: 16px;
}

.slidedeck-thumbnails h5 {
    font-size: 14px;
    color: var(--gray-600);
    margin-bottom: 12px;
}

.slidedeck-thumbnails-list {
    display: flex;
    gap: 8px;
    overflow-x: auto;
    padding-bottom: 8px;
}

.slidedeck-thumbnail {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
    padding: 8px 12px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-sm);
    cursor: pointer;
    min-width: 80px;
    transition: all 0.15s;
}

.slidedeck-thumbnail:hover {
    border-color: var(--primary);
    background: var(--gray-50);
}

.slidedeck-thumbnail.active {
    border-color: #7C3AED;
    background: #EDE9FE;
}

.slidedeck-thumbnail .slide-number {
    font-size: 14px;
    font-weight: 600;
    color: var(--gray-600);
}

.slidedeck-thumbnail.active .slide-number {
    color: #7C3AED;
}

.slidedeck-thumbnail .slide-preview {
    font-size: 11px;
    color: var(--gray-500);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 70px;
}

/* ============================================================
   Study Guide Styles
   ============================================================ */
.studyguide-container {
    max-width: 800px;
    margin: 0 auto;
}

.studyguide-title {
    font-size: 28px;
    color: var(--gray-800);
    text-align: center;
    margin-bottom: 24px;
    padding-bottom: 16px;
    border-bottom: 2px solid var(--primary);
}

.studyguide-overview {
    background: var(--primary-light);
    border-radius: var(--radius);
    padding: 20px;
    margin-bottom: 24px;
}

.studyguide-overview h3 {
    font-size: 16px;
    color: var(--primary);
    margin-bottom: 12px;
}

.studyguide-overview p {
    font-size: 15px;
    line-height: 1.7;
    color: var(--gray-700);
    margin: 0;
}

.studyguide-sections {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.studyguide-section {
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    padding: 20px;
}

.studyguide-section .section-title {
    font-size: 18px;
    color: var(--gray-800);
    margin-bottom: 16px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--gray-200);
}

.studyguide-section .section-content {
    font-size: 14px;
    line-height: 1.7;
    color: var(--gray-700);
    margin-bottom: 16px;
}

.studyguide-section .section-key-points {
    background: var(--gray-50);
    border-radius: var(--radius-sm);
    padding: 16px;
    margin-bottom: 16px;
}

.studyguide-section .section-key-points strong {
    display: block;
    font-size: 13px;
    color: var(--gray-600);
    margin-bottom: 8px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.studyguide-section .section-key-points ul {
    margin: 0;
    padding-left: 20px;
}

.studyguide-section .section-key-points li {
    font-size: 14px;
    color: var(--gray-700);
    margin-bottom: 6px;
    line-height: 1.5;
}

.studyguide-section .section-terms {
    background: #FEF3C7;
    border-radius: var(--radius-sm);
    padding: 16px;
    margin-bottom: 16px;
}

.studyguide-section .section-terms strong {
    display: block;
    font-size: 13px;
    color: #92400E;
    margin-bottom: 8px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.studyguide-section .section-terms dl {
    margin: 0;
}

.studyguide-section .section-terms dt {
    font-weight: 600;
    color: var(--gray-800);
    margin-top: 8px;
}

.studyguide-section .section-terms dt:first-child {
    margin-top: 0;
}

.studyguide-section .section-terms dd {
    margin: 4px 0 0 16px;
    font-size: 14px;
    color: var(--gray-700);
    line-height: 1.5;
}

.studyguide-section .section-questions {
    background: #DBEAFE;
    border-radius: var(--radius-sm);
    padding: 16px;
}

.studyguide-section .section-questions strong {
    display: block;
    font-size: 13px;
    color: #1E40AF;
    margin-bottom: 8px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.studyguide-section .section-questions ol {
    margin: 0;
    padding-left: 20px;
}

.studyguide-section .section-questions li {
    font-size: 14px;
    color: var(--gray-700);
    margin-bottom: 8px;
    line-height: 1.5;
}

.studyguide-summary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-hover) 100%);
    border-radius: var(--radius);
    padding: 24px;
    margin-top: 24px;
}

.studyguide-summary h3 {
    font-size: 16px;
    color: white;
    margin-bottom: 12px;
}

.studyguide-summary p {
    font-size: 15px;
    line-height: 1.7;
    color: rgba(255,255,255,0.9);
    margin: 0;
}

/* ============================================================
   Infographic Styles
   ============================================================ */
.infographic-container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

.infographic-title {
    font-size: 32px;
    color: var(--gray-800);
    text-align: center;
    margin-bottom: 8px;
}

.infographic-subtitle {
    font-size: 16px;
    color: var(--gray-500);
    text-align: center;
    margin-bottom: 32px;
}

.infographic-sections {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    margin-bottom: 32px;
}

.infographic-section {
    display: flex;
    gap: 16px;
    background: white;
    border-radius: var(--radius);
    padding: 20px;
    border-left: 4px solid var(--section-color, var(--primary));
    box-shadow: var(--shadow-sm);
    transition: transform 0.15s, box-shadow 0.15s;
}

.infographic-section:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.infographic-icon {
    width: 48px;
    height: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--gray-100);
    border-radius: var(--radius);
    color: var(--section-color, var(--primary));
    flex-shrink: 0;
}

.infographic-icon svg {
    stroke: currentColor;
}

.infographic-section-content {
    flex: 1;
}

.infographic-section-content h4 {
    font-size: 16px;
    color: var(--gray-800);
    margin-bottom: 4px;
}

.infographic-stat {
    font-size: 24px;
    font-weight: 700;
    color: var(--section-color, var(--primary));
    margin-bottom: 8px;
}

.infographic-section-content p {
    font-size: 14px;
    color: var(--gray-600);
    line-height: 1.5;
    margin: 0;
}

.infographic-flow {
    background: var(--gray-50);
    border-radius: var(--radius);
    padding: 24px;
    margin-bottom: 24px;
}

.infographic-flow h3 {
    font-size: 16px;
    color: var(--gray-600);
    text-align: center;
    margin-bottom: 20px;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.flow-steps {
    display: flex;
    align-items: center;
    justify-content: center;
    flex-wrap: wrap;
    gap: 12px;
}

.flow-step {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    padding: 16px;
    background: white;
    border-radius: var(--radius);
    box-shadow: var(--shadow-sm);
    min-width: 100px;
}

.flow-number {
    width: 36px;
    height: 36px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--primary);
    color: white;
    font-weight: 700;
    font-size: 16px;
    border-radius: 50%;
}

.flow-label {
    font-size: 13px;
    color: var(--gray-700);
    text-align: center;
    font-weight: 500;
}

.flow-arrow {
    font-size: 24px;
    color: var(--gray-400);
    font-weight: 300;
}

.infographic-takeaway {
    background: linear-gradient(135deg, #059669 0%, #047857 100%);
    border-radius: var(--radius);
    padding: 20px;
    color: white;
    text-align: center;
}

.infographic-takeaway strong {
    display: block;
    font-size: 12px;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 8px;
    opacity: 0.9;
}

.infographic-takeaway {
    font-size: 16px;
    line-height: 1.6;
}

/* ============================================================
   Summary Styles
   ============================================================ */
.summary-container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

.summary-title {
    font-size: 28px;
    color: var(--gray-800);
    margin-bottom: 24px;
    padding-bottom: 16px;
    border-bottom: 2px solid var(--primary);
}

.summary-overview {
    background: linear-gradient(135deg, var(--primary) 0%, #4338CA 100%);
    border-radius: var(--radius);
    padding: 24px;
    margin-bottom: 24px;
    color: white;
}

.summary-overview h3 {
    font-size: 14px;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 12px;
    opacity: 0.9;
}

.summary-overview p {
    font-size: 16px;
    line-height: 1.7;
    margin: 0;
}

.summary-sections {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.summary-section {
    background: white;
    border-radius: var(--radius);
    padding: 24px;
    border-left: 4px solid var(--primary);
    box-shadow: var(--shadow-sm);
}

.summary-section h4 {
    font-size: 18px;
    color: var(--gray-800);
    margin-bottom: 12px;
}

.summary-section > p {
    font-size: 15px;
    line-height: 1.7;
    color: var(--gray-700);
    margin-bottom: 16px;
}

.summary-key-points {
    list-style: none;
    padding: 0;
    margin: 16px 0;
}

.summary-key-points li {
    position: relative;
    padding-left: 24px;
    margin-bottom: 10px;
    font-size: 14px;
    color: var(--gray-700);
    line-height: 1.5;
}

.summary-key-points li::before {
    content: "•";
    position: absolute;
    left: 8px;
    color: var(--primary);
    font-weight: bold;
    font-size: 18px;
}

.summary-highlights {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 12px;
}

.highlight-tag {
    display: inline-block;
    padding: 4px 12px;
    background: var(--gray-100);
    color: var(--primary);
    border-radius: 16px;
    font-size: 13px;
    font-weight: 500;
}

.summary-conclusion {
    background: var(--gray-50);
    border-radius: var(--radius);
    padding: 24px;
    margin-top: 24px;
}

.summary-conclusion h3 {
    font-size: 16px;
    color: var(--gray-800);
    margin-bottom: 12px;
}

.summary-conclusion p {
    font-size: 15px;
    line-height: 1.7;
    color: var(--gray-700);
    margin: 0;
}

/* ============================================================
   Critique Styles
   ============================================================ */
.critique-container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
}

.critique-title {
    font-size: 28px;
    color: var(--gray-800);
    margin-bottom: 24px;
}

.critique-assessment {
    background: white;
    border-radius: var(--radius);
    padding: 24px;
    margin-bottom: 24px;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--gray-200);
}

.critique-rating {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 16px;
}

.rating-label {
    font-size: 14px;
    color: var(--gray-600);
    font-weight: 500;
}

.rating-value {
    display: inline-block;
    padding: 6px 16px;
    background: var(--rating-color, var(--gray-500));
    color: white;
    border-radius: 20px;
    font-weight: 600;
    font-size: 14px;
}

.assessment-text {
    font-size: 15px;
    line-height: 1.7;
    color: var(--gray-700);
    margin: 0;
}

.critique-summary-boxes {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 20px;
    margin-bottom: 24px;
}

.critique-box {
    background: white;
    border-radius: var(--radius);
    padding: 20px;
    box-shadow: var(--shadow-sm);
}

.critique-strengths {
    border-left: 4px solid #059669;
}

.critique-weaknesses {
    border-left: 4px solid #DC2626;
}

.critique-box h4 {
    font-size: 16px;
    margin-bottom: 12px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.critique-strengths h4 {
    color: #059669;
}

.critique-weaknesses h4 {
    color: #DC2626;
}

.box-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 24px;
    height: 24px;
    border-radius: 50%;
    font-weight: bold;
    font-size: 18px;
}

.critique-strengths .box-icon {
    background: #ECFDF5;
    color: #059669;
}

.critique-weaknesses .box-icon {
    background: #FEF2F2;
    color: #DC2626;
}

.critique-box ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.critique-box li {
    position: relative;
    padding-left: 20px;
    margin-bottom: 8px;
    font-size: 14px;
    color: var(--gray-700);
    line-height: 1.5;
}

.critique-box li::before {
    content: "•";
    position: absolute;
    left: 4px;
    font-weight: bold;
}

.critique-strengths li::before {
    color: #059669;
}

.critique-weaknesses li::before {
    color: #DC2626;
}

.critique-analysis {
    margin-bottom: 24px;
}

.critique-analysis h3 {
    font-size: 18px;
    color: var(--gray-800);
    margin-bottom: 16px;
    padding-bottom: 8px;
    border-bottom: 1px solid var(--gray-200);
}

.analysis-item {
    background: white;
    border-radius: var(--radius);
    padding: 20px;
    margin-bottom: 16px;
    box-shadow: var(--shadow-sm);
    border-left: 4px solid var(--category-color, var(--gray-400));
}

.analysis-header {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 12px;
}

.analysis-category {
    display: inline-block;
    padding: 4px 12px;
    background: var(--category-color, var(--gray-400));
    color: white;
    border-radius: 4px;
    font-size: 12px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.analysis-heading {
    font-size: 16px;
    font-weight: 600;
    color: var(--gray-800);
}

.analysis-points {
    list-style: none;
    padding: 0;
    margin: 0 0 12px 0;
}

.analysis-points li {
    position: relative;
    padding-left: 20px;
    margin-bottom: 8px;
    font-size: 14px;
    color: var(--gray-700);
}

.analysis-points li::before {
    content: "→";
    position: absolute;
    left: 0;
    color: var(--category-color, var(--gray-400));
}

.analysis-explanation {
    font-size: 14px;
    line-height: 1.6;
    color: var(--gray-600);
    margin: 0;
    padding-top: 8px;
    border-top: 1px solid var(--gray-100);
}

.critique-recommendations {
    background: linear-gradient(135deg, #7C3AED 0%, #5B21B6 100%);
    border-radius: var(--radius);
    padding: 24px;
    color: white;
}

.critique-recommendations h3 {
    font-size: 16px;
    margin-bottom: 16px;
    text-transform: uppercase;
    letter-spacing: 1px;
    opacity: 0.9;
}

.critique-recommendations ul {
    list-style: none;
    padding: 0;
    margin: 0;
}

.critique-recommendations li {
    position: relative;
    padding-left: 28px;
    margin-bottom: 12px;
    font-size: 15px;
    line-height: 1.6;
}

.critique-recommendations li::before {
    content: "✓";
    position: absolute;
    left: 0;
    width: 20px;
    height: 20px;
    background: rgba(255,255,255,0.2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
}

/* ============================================================
   Statistics Styles
   ============================================================ */
.statistics-container {
    padding: 20px;
}

.statistics-header {
    text-align: center;
    margin-bottom: 24px;
    padding-bottom: 16px;
    border-bottom: 2px solid var(--primary);
}

.statistics-header h4 {
    font-size: 24px;
    color: var(--gray-800);
    margin-bottom: 4px;
}

.statistics-header .stats-subject {
    font-size: 14px;
    color: var(--gray-500);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.statistics-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 16px;
    margin-bottom: 24px;
}

.stat-card {
    background: var(--gray-50);
    border-radius: var(--radius);
    padding: 20px;
    text-align: center;
    border: 1px solid var(--gray-200);
    transition: all 0.15s;
}

.stat-card:hover {
    border-color: var(--primary);
    background: var(--primary-light);
}

.stat-card .stat-icon {
    width: 40px;
    height: 40px;
    margin: 0 auto 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--primary);
    color: white;
    border-radius: 50%;
}

.stat-card .stat-icon svg {
    width: 20px;
    height: 20px;
}

.stat-card .stat-value {
    font-size: 28px;
    font-weight: 700;
    color: var(--gray-800);
    margin-bottom: 4px;
}

.stat-card .stat-label {
    font-size: 13px;
    color: var(--gray-500);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.statistics-details {
    background: white;
    border-radius: var(--radius);
    border: 1px solid var(--gray-200);
    overflow: hidden;
}

.statistics-details h5 {
    font-size: 14px;
    color: var(--gray-600);
    padding: 12px 16px;
    background: var(--gray-50);
    border-bottom: 1px solid var(--gray-200);
    margin: 0;
}

.stat-detail-row {
    display: flex;
    justify-content: space-between;
    padding: 12px 16px;
    border-bottom: 1px solid var(--gray-100);
}

.stat-detail-row:last-child {
    border-bottom: none;
}

.stat-detail-row .detail-label {
    color: var(--gray-600);
    font-size: 14px;
}

.stat-detail-row .detail-value {
    color: var(--gray-800);
    font-weight: 500;
    font-size: 14px;
}

.stat-detail-row .detail-value.editable {
    color: var(--primary);
    cursor: pointer;
}

.stat-detail-row .detail-value.editable:hover {
    text-decoration: underline;
}

.complexity-badge {
    display: inline-block;
    padding: 4px 12px;
    border-radius: 12px;
    font-size: 12px;
    font-weight: 600;
}

.complexity-easy {
    background: #D1FAE5;
    color: #065F46;
}

.complexity-moderate {
    background: #FEF3C7;
    color: #92400E;
}

.complexity-challenging {
    background: #FEE2E2;
    color: #991B1B;
}

.reading-time-breakdown {
    margin-top: 24px;
    padding: 20px;
    background: linear-gradient(135deg, var(--primary) 0%, #4338CA 100%);
    border-radius: var(--radius);
    color: white;
}

.reading-time-breakdown h5 {
    font-size: 14px;
    margin-bottom: 16px;
    opacity: 0.9;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.reading-schedule {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
    text-align: center;
}

.schedule-item .schedule-value {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 4px;
}

.schedule-item .schedule-label {
    font-size: 12px;
    opacity: 0.8;
}

/* ============================================================
   Albert Chatbot Styles
   ============================================================ */
.header-logo {
    cursor: pointer;
}

.chatbot-overlay {
    position: fixed;
    bottom: 20px;
    right: 20px;
    z-index: 1000;
}

.chatbot-container {
    width: 380px;
    max-width: calc(100vw - 40px);
    height: 520px;
    max-height: calc(100vh - 120px);
    background: white;
    border-radius: var(--radius-lg);
    box-shadow: 0 10px 40px rgba(0,0,0,0.2);
    display: flex;
    flex-direction: column;
    overflow: hidden;
    animation: chatbot-slide-up 0.3s ease-out;
}

.chatbot-container.dragging {
    animation: none;
}

@keyframes chatbot-slide-up {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.chatbot-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px;
    background: linear-gradient(135deg, #4F46E5 0%, #7C3AED 100%);
    color: white;
    cursor: move;
    user-select: none;
}

.chatbot-header-info {
    display: flex;
    align-items: center;
    gap: 12px;
}

.chatbot-avatar-small {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 2px solid rgba(255,255,255,0.3);
    object-fit: cover;
    object-position: center top;
}

.chatbot-header h3 {
    font-size: 16px;
    margin: 0;
}

.chatbot-status {
    font-size: 12px;
    opacity: 0.8;
}

.chatbot-header .btn-close {
    color: white;
    opacity: 0.8;
    background: transparent;
}

.chatbot-header .btn-close:hover {
    opacity: 1;
    background: rgba(255, 255, 255, 0.2);
    color: white;
}

.chatbot-messages {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
    background: var(--gray-50);
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.chatbot-welcome {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding: 20px 0;
}

.chatbot-avatar-large {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    border: 3px solid var(--primary);
    margin-bottom: 16px;
    object-fit: cover;
    object-position: center center;
}

.chatbot-bubble {
    background: white;
    border-radius: 18px;
    border-top-left-radius: 4px;
    padding: 12px 16px;
    box-shadow: var(--shadow-sm);
    max-width: 85%;
    position: relative;
}

.chatbot-bubble p {
    margin: 0;
    font-size: 14px;
    line-height: 1.5;
    color: var(--gray-700);
}

.chatbot-message {
    display: flex;
    gap: 10px;
    align-items: flex-start;
}

.chatbot-message.user {
    flex-direction: row-reverse;
}

.chatbot-message .avatar {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    flex-shrink: 0;
    object-fit: cover;
}

.chatbot-message.user .avatar {
    background: var(--primary);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: 600;
    font-size: 14px;
}

.chatbot-message .bubble {
    background: white;
    border-radius: 18px;
    padding: 10px 14px;
    box-shadow: var(--shadow-sm);
    max-width: 75%;
}

.chatbot-message.bot .bubble {
    border-top-left-radius: 4px;
    background: white;
}

.chatbot-message.user .bubble {
    border-top-right-radius: 4px;
    background: var(--primary);
    color: white;
}

.chatbot-message .bubble p {
    margin: 0;
    font-size: 14px;
    line-height: 1.5;
}

.chatbot-message.bot .bubble p {
    color: var(--gray-700);
}

.chatbot-typing {
    display: flex;
    gap: 4px;
    padding: 8px 0;
}

.chatbot-typing span {
    width: 8px;
    height: 8px;
    background: var(--gray-400);
    border-radius: 50%;
    animation: typing-bounce 1.4s infinite ease-in-out;
}

.chatbot-typing span:nth-child(1) {
    animation-delay: 0s;
}

.chatbot-typing span:nth-child(2) {
    animation-delay: 0.2s;
}

.chatbot-typing span:nth-child(3) {
    animation-delay: 0.4s;
}

@keyframes typing-bounce {
    0%, 60%, 100% {
        transform: translateY(0);
    }
    30% {
        transform: translateY(-8px);
    }
}

.chatbot-input-area {
    display: flex;
    gap: 8px;
    padding: 12px 16px;
    background: white;
    border-top: 1px solid var(--gray-200);
    align-items: center;
}

.chatbot-input-area input {
    flex: 1;
    padding: 10px 14px;
    border: 1px solid var(--gray-300);
    border-radius: 20px;
    font-size: 14px;
    outline: none;
    transition: border-color 0.15s;
}

.chatbot-input-area input:focus {
    border-color: var(--primary);
}

.chatbot-input-area button {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    padding: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.chatbot-input-area button svg {
    margin-left: 2px;
}

/* Voice Control Buttons */
.chatbot-input-area .btn-voice {
    width: 36px;
    height: 36px;
    background: var(--gray-100);
    border: 1px solid var(--gray-300);
    color: var(--gray-600);
    cursor: pointer;
    transition: all 0.2s;
}

.chatbot-input-area .btn-voice:hover {
    background: var(--gray-200);
    color: var(--gray-700);
}

.chatbot-input-area .btn-voice svg {
    margin-left: 0;
    width: 18px;
    height: 18px;
}

/* Microphone button - listening state */
.chatbot-input-area .btn-mic.listening {
    background: #EF4444;
    border-color: #EF4444;
    color: white;
    animation: pulse-mic 1.5s infinite;
}

@keyframes pulse-mic {
    0%, 100% {
        box-shadow: 0 0 0 0 rgba(239, 68, 68, 0.4);
    }
    50% {
        box-shadow: 0 0 0 8px rgba(239, 68, 68, 0);
    }
}

/* Speaker button - speaking state */
.chatbot-input-area .btn-speak.speaking {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
    animation: pulse-speak 1s infinite;
}

@keyframes pulse-speak {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.7;
    }
}

/* ============================================================
   Connections Styles
   ============================================================ */
.connections-container {
    padding: 20px;
}

.connections-summary {
    background: var(--primary-light);
    border: 1px solid var(--primary);
    border-radius: var(--radius);
    padding: 16px;
    margin-bottom: 24px;
}

.connections-summary p {
    margin: 0;
    color: var(--gray-700);
    font-size: 14px;
    line-height: 1.6;
}

.connections-category {
    margin-bottom: 24px;
}

.connections-category:last-of-type {
    margin-bottom: 16px;
}

.connections-category-header {
    display: flex;
    align-items: center;
    gap: 10px;
    padding-bottom: 12px;
    border-bottom: 2px solid var(--primary);
    margin-bottom: 16px;
}

.connections-category-header svg {
    color: var(--primary);
    flex-shrink: 0;
}

.connections-category-header h4 {
    margin: 0;
    font-size: 16px;
    font-weight: 600;
    color: var(--gray-800);
}

.connections-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.connection-item {
    background: var(--gray-50);
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    padding: 16px;
    transition: all 0.15s;
}

.connection-item:hover {
    border-color: var(--primary);
    background: white;
}

.connection-sources {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-bottom: 10px;
}

.connection-source-tag {
    display: inline-block;
    background: var(--primary);
    color: white;
    font-size: 11px;
    font-weight: 500;
    padding: 3px 10px;
    border-radius: 12px;
}

.connection-title {
    font-weight: 600;
    font-size: 14px;
    color: var(--gray-800);
    margin-bottom: 6px;
}

.connection-description {
    font-size: 13px;
    color: var(--gray-600);
    line-height: 1.5;
}

.connections-insights {
    background: var(--gray-50);
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    padding: 16px;
    margin-top: 24px;
}

.connections-insights h4 {
    margin: 0 0 12px 0;
    font-size: 14px;
    font-weight: 600;
    color: var(--gray-800);
}

.connections-insights ul {
    margin: 0;
    padding-left: 20px;
}

.connections-insights li {
    color: var(--gray-600);
    font-size: 13px;
    line-height: 1.6;
    margin-bottom: 8px;
}

.connections-insights li:last-child {
    margin-bottom: 0;
}

/* ============================================================
   Reader Paste Area (when no source exists)
   ============================================================ */
.reader-paste-area {
    display: flex;
    flex-direction: column;
    height: 100%;
    padding: 20px;
}

.reader-paste-area label {
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-700);
    margin-bottom: 12px;
}

.paste-textarea {
    flex: 1;
    min-height: 200px;
    padding: 16px;
    font-size: 14px;
    font-family: var(--font);
    line-height: 1.6;
    color: var(--gray-800);
    background: white;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius);
    resize: none;
}

.paste-textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}

.paste-textarea::placeholder {
    color: var(--gray-400);
}

.paste-actions {
    display: flex;
    gap: 12px;
    margin-top: 16px;
    align-items: center;
}

.paste-title-input {
    flex: 1;
    padding: 10px 12px;
    font-size: 14px;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius);
}

.paste-title-input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px var(--primary-light);
}

/* ============================================================
   Tools Header Icons
   ============================================================ */
.header-right-icons {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 12px;
    flex-shrink: 0;
    justify-content: flex-end;
    padding-right: 16px;
}

.nav-icon-tools {
    padding: 0;
    border: none;
    background: transparent;
    cursor: pointer;
    transition: opacity 0.15s;
    display: flex;
    align-items: center;
    justify-content: center;
    outline: none;
}

.nav-icon-tools:hover {
    opacity: 0.8;
}

.nav-icon-tools img {
    height: 45px;
    width: auto;
    object-fit: contain;
}

/* ============================================================
   Tools Modal (Main Grid)
   ============================================================ */
.tools-modal-content {
    width: 420px;
    max-width: 90vw;
}

.tools-modal-body {
    padding: 20px;
}

.tools-grid {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.tool-card {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 16px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    cursor: pointer;
    transition: all 0.15s;
}

.tool-card:hover {
    border-color: var(--primary);
    background: var(--primary-light);
    transform: translateY(-2px);
    box-shadow: var(--shadow);
}

.tool-card-icon {
    width: 52px;
    height: 52px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 12px;
    flex-shrink: 0;
}

.tool-card-icon.calc-icon {
    background: linear-gradient(135deg, #3B82F6, #1D4ED8);
    color: white;
}

.tool-card-icon.converter-icon {
    background: linear-gradient(135deg, #10B981, #059669);
    color: white;
}

.tool-card-icon.qr-icon {
    background: linear-gradient(135deg, #8B5CF6, #6D28D9);
    color: white;
}

.tool-card-icon.grammar-icon {
    background: linear-gradient(135deg, #F59E0B, #D97706);
    color: white;
}

.tool-card-info h4 {
    font-size: 15px;
    font-weight: 600;
    color: var(--gray-800);
    margin: 0 0 4px 0;
}

.tool-card-info p {
    font-size: 13px;
    color: var(--gray-500);
    margin: 0;
}

/* ============================================================
   Tool Modals (Draggable Floating Windows)
   ============================================================ */
.tool-modal {
    position: fixed;
    z-index: 10000;
    background: white;
    border-radius: 12px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.25), 0 8px 20px rgba(0, 0, 0, 0.15);
    opacity: 0;
    visibility: hidden;
    transform: scale(0.95) translateY(10px);
    transition: opacity 0.2s, visibility 0.2s, transform 0.2s;
    min-width: 280px;
    overflow: hidden;
}

.tool-modal.open {
    opacity: 1;
    visibility: visible;
    transform: scale(1) translateY(0);
}

.tool-modal.minimized .tool-modal-body {
    display: none;
}

.tool-modal.minimized {
    min-width: auto;
}

.tool-modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 12px;
    background: linear-gradient(135deg, #3B82F6, #1D4ED8);
    color: white;
    cursor: move;
    user-select: none;
}

.converter-header {
    background: linear-gradient(135deg, #10B981, #059669);
}

.qr-header {
    background: linear-gradient(135deg, #8B5CF6, #6D28D9);
}

.tool-modal-title {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 600;
    font-size: 14px;
}

.tool-modal-controls {
    display: flex;
    gap: 6px;
}

.tool-modal-btn {
    width: 14px;
    height: 14px;
    border-radius: 50%;
    border: none;
    cursor: pointer;
    transition: transform 0.1s;
}

.tool-modal-btn:hover {
    transform: scale(1.2);
}

.tool-modal-btn.minimize {
    background: #FBBF24;
}

.tool-modal-btn.close {
    background: #EF4444;
}

.tool-modal-body {
    padding: 16px;
    background: #f8f9fa;
}

/* ============================================================
   Calculator Styles
   ============================================================ */
.calc-modal {
    width: 300px;
}

.calc-modal.scientific-mode {
    width: 340px;
}

.calc-mode-toggle {
    display: flex;
    gap: 8px;
    margin-bottom: 12px;
}

.calc-mode-btn {
    flex: 1;
    padding: 8px;
    border: 1px solid var(--gray-300);
    background: white;
    border-radius: 6px;
    font-size: 13px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.15s;
    color: var(--gray-600);
}

.calc-mode-btn.active {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
}

.calc-mode-btn:hover:not(.active) {
    border-color: var(--primary);
    background: var(--primary-light);
}

.calc-display {
    background: white;
    border-radius: 8px;
    padding: 12px;
    margin-bottom: 12px;
    text-align: right;
    border: 1px solid var(--gray-200);
}

.calc-expression {
    font-size: 12px;
    color: var(--gray-500);
    min-height: 16px;
    margin-bottom: 4px;
}

.calc-result {
    font-size: 28px;
    font-weight: 600;
    color: var(--gray-800);
    overflow-x: auto;
    white-space: nowrap;
}

.calc-scientific {
    display: none;
    grid-template-columns: repeat(5, 1fr);
    gap: 6px;
    margin-bottom: 8px;
}

.calc-modal.scientific-mode .calc-scientific {
    display: grid;
}

.calc-buttons {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 6px;
}

.calc-btn {
    padding: 14px 8px;
    font-size: 16px;
    font-weight: 500;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.1s;
}

.calc-btn:hover {
    transform: scale(1.05);
}

.calc-btn:active {
    transform: scale(0.98);
}

.calc-btn.number {
    background: white;
    color: var(--gray-800);
    border: 1px solid var(--gray-200);
}

.calc-btn.number:hover {
    background: var(--gray-100);
}

.calc-btn.zero {
    grid-column: span 2;
}

.calc-btn.function {
    background: var(--gray-200);
    color: var(--gray-800);
}

.calc-btn.function:hover {
    background: var(--gray-300);
}

.calc-btn.operator {
    background: var(--primary);
    color: white;
}

.calc-btn.operator:hover {
    background: var(--primary-hover);
}

.calc-btn.equals {
    background: #10B981;
    color: white;
}

.calc-btn.equals:hover {
    background: #059669;
}

.calc-btn.scientific {
    background: white;
    color: var(--gray-700);
    border: 1px solid var(--gray-200);
    font-size: 13px;
    padding: 10px 6px;
}

.calc-btn.scientific:hover {
    background: var(--primary-light);
    border-color: var(--primary);
}

/* Calculator History */
.calc-history {
    margin-top: 12px;
    border-radius: 8px;
    background: white;
    border: 1px solid var(--gray-200);
    overflow: hidden;
}

.calc-history-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 12px;
    background: var(--gray-50);
    cursor: pointer;
    user-select: none;
}

.calc-history-title {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 13px;
    font-weight: 500;
    color: var(--gray-600);
}

.calc-history-title svg {
    transition: transform 0.2s;
}

.calc-history.collapsed .calc-history-title svg {
    transform: rotate(-90deg);
}

.calc-clear-history {
    font-size: 12px;
    color: var(--gray-500);
    background: none;
    border: none;
    cursor: pointer;
    padding: 2px 8px;
    border-radius: 4px;
}

.calc-clear-history:hover {
    background: var(--gray-200);
    color: var(--gray-700);
}

.calc-history-content {
    max-height: 150px;
    overflow-y: auto;
}

.calc-history.collapsed .calc-history-content {
    display: none;
}

.calc-history-list {
    padding: 8px;
}

.calc-history-item {
    font-size: 13px;
    color: var(--gray-600);
    padding: 6px 8px;
    border-radius: 4px;
}

.calc-history-item:hover {
    background: var(--gray-100);
}

.calc-history-empty {
    font-size: 13px;
    color: var(--gray-400);
    padding: 12px;
    text-align: center;
}

/* ============================================================
   Unit Converter Styles
   ============================================================ */
.converter-modal {
    width: 320px;
}

.converter-categories {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-bottom: 16px;
}

.converter-category-btn {
    padding: 6px 12px;
    font-size: 12px;
    font-weight: 500;
    border: 1px solid var(--gray-300);
    background: white;
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.15s;
    color: var(--gray-600);
}

.converter-category-btn.active {
    background: #10B981;
    border-color: #10B981;
    color: white;
}

.converter-category-btn:hover:not(.active) {
    border-color: #10B981;
    background: #D1FAE5;
}

.converter-fields {
    display: flex;
    flex-direction: column;
    gap: 12px;
    align-items: center;
}

.converter-field {
    width: 100%;
}

.converter-field label {
    display: block;
    font-size: 12px;
    font-weight: 500;
    color: var(--gray-500);
    margin-bottom: 4px;
}

.converter-input {
    width: 100%;
    padding: 10px 12px;
    font-size: 16px;
    border: 1px solid var(--gray-300);
    border-radius: 8px;
    margin-bottom: 6px;
}

.converter-input:focus {
    outline: none;
    border-color: #10B981;
    box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.15);
}

.converter-select {
    width: 100%;
    padding: 8px 12px;
    font-size: 14px;
    border: 1px solid var(--gray-300);
    border-radius: 8px;
    background: white;
    cursor: pointer;
}

.converter-select:focus {
    outline: none;
    border-color: #10B981;
}

.converter-swap-btn {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 2px solid var(--gray-300);
    background: white;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--gray-500);
    transition: all 0.15s;
    margin: -6px 0;
}

.converter-swap-btn:hover {
    border-color: #10B981;
    color: #10B981;
    background: #D1FAE5;
}

.converter-formula {
    margin-top: 12px;
    padding: 10px;
    background: white;
    border-radius: 8px;
    font-size: 13px;
    color: var(--gray-600);
    text-align: center;
    border: 1px solid var(--gray-200);
    min-height: 20px;
}

/* ============================================================
   QR Code Generator Styles
   ============================================================ */
.qr-modal {
    width: 320px;
}

.qr-type-tabs {
    display: flex;
    gap: 6px;
    margin-bottom: 16px;
}

.qr-type-btn {
    flex: 1;
    padding: 8px 12px;
    font-size: 13px;
    font-weight: 500;
    border: 1px solid var(--gray-300);
    background: white;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.15s;
    color: var(--gray-600);
}

.qr-type-btn.active {
    background: #8B5CF6;
    border-color: #8B5CF6;
    color: white;
}

.qr-type-btn:hover:not(.active) {
    border-color: #8B5CF6;
    background: #EDE9FE;
}

.qr-input-area {
    margin-bottom: 16px;
}

.qr-field {
    margin-bottom: 10px;
}

.qr-field:last-child {
    margin-bottom: 0;
}

.qr-input {
    width: 100%;
    padding: 10px 12px;
    font-size: 14px;
    border: 1px solid var(--gray-300);
    border-radius: 8px;
}

.qr-input:focus {
    outline: none;
    border-color: #8B5CF6;
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.15);
}

.qr-textarea {
    min-height: 80px;
    resize: vertical;
    font-family: var(--font);
}

.qr-generate-btn {
    width: 100%;
    padding: 12px;
    font-size: 14px;
    font-weight: 600;
    border: none;
    border-radius: 8px;
    background: #8B5CF6;
    color: white;
    cursor: pointer;
    transition: background 0.15s;
    margin-bottom: 16px;
}

.qr-generate-btn:hover {
    background: #7C3AED;
}

.qr-output {
    text-align: center;
}

.qr-preview {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 60px;
    padding: 16px;
    background: white;
    border-radius: 8px;
    border: 1px solid var(--gray-200);
}

.qr-preview img {
    max-width: 180px;
}

.qr-preview canvas {
    display: none;
}

.qr-actions {
    display: flex;
    gap: 8px;
    margin-top: 12px;
    justify-content: center;
}

.qr-action-btn {
    padding: 8px 16px;
    font-size: 13px;
    font-weight: 500;
    border: 1px solid var(--gray-300);
    background: white;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.15s;
    color: var(--gray-700);
}

.qr-action-btn:hover {
    border-color: #8B5CF6;
    background: #EDE9FE;
    color: #8B5CF6;
}

/* ============================================================
   World Atlas Tool
   ============================================================ */
.tool-card-icon.atlas-icon {
    background: linear-gradient(135deg, #06B6D4, #0891B2);
    color: white;
}

.atlas-modal-content {
    width: 90vw;
    max-width: 900px;
    height: 80vh;
    max-height: 700px;
    display: flex;
    flex-direction: column;
}

.atlas-modal-header {
    background: linear-gradient(135deg, #06B6D4, #0891B2);
    color: white;
    padding: 12px 16px;
    border-radius: var(--radius-lg) var(--radius-lg) 0 0;
}

.atlas-modal-header h3 {
    margin: 0;
    font-size: 18px;
}

.atlas-modal-header .close-btn {
    color: white;
}

.atlas-modal-header .close-btn:hover {
    background: rgba(255, 255, 255, 0.2);
    color: white;
}

.atlas-modal-body {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: #f8f9fa;
}

.atlas-controls {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    padding: 12px 16px;
    background: white;
    border-bottom: 1px solid var(--gray-200);
}

.atlas-search {
    display: flex;
    gap: 8px;
    flex: 1;
    max-width: 400px;
}

.atlas-search input {
    flex: 1;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
}

.atlas-search input:focus {
    outline: none;
    border-color: #06B6D4;
    box-shadow: 0 0 0 3px rgba(6, 182, 212, 0.15);
}

.atlas-layers {
    display: flex;
    gap: 6px;
}

.atlas-layer-btn {
    padding: 6px 14px;
    font-size: 13px;
    font-weight: 500;
    border: 1px solid var(--gray-300);
    background: white;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.15s;
    color: var(--gray-600);
}

.atlas-layer-btn.active {
    background: #06B6D4;
    border-color: #06B6D4;
    color: white;
}

.atlas-layer-btn:hover:not(.active) {
    border-color: #06B6D4;
    background: #ECFEFF;
}

.atlas-map-container {
    flex: 1;
    position: relative;
    min-height: 300px;
}

#atlasMap {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 1;
}

.atlas-info-panel {
    padding: 12px 16px;
    background: white;
    border-top: 1px solid var(--gray-200);
    min-height: 80px;
    max-height: 120px;
    overflow-y: auto;
}

.atlas-info-hint {
    color: var(--gray-500);
    font-size: 14px;
    margin: 0;
    text-align: center;
    padding: 16px 0;
}

.atlas-info-loading {
    color: var(--gray-500);
    font-size: 14px;
    margin: 0;
    text-align: center;
}

.atlas-info-error {
    color: var(--danger);
    font-size: 14px;
    margin: 0;
    text-align: center;
}

.atlas-location-info h4 {
    margin: 0 0 8px 0;
    font-size: 16px;
    color: var(--gray-800);
}

.atlas-country {
    margin: 0 0 8px 0;
    font-size: 14px;
    color: #06B6D4;
}

.atlas-details {
    display: flex;
    flex-wrap: wrap;
    gap: 8px 24px;
}

.atlas-details p {
    margin: 0;
    font-size: 13px;
    color: var(--gray-600);
}

.atlas-details span {
    color: var(--gray-500);
}

.atlas-type {
    margin: 8px 0 0 0;
    font-size: 12px;
    color: var(--gray-400);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* ============================================================
   Math Solver Tool
   ============================================================ */
.tool-card-icon.math-solver-icon {
    background: linear-gradient(135deg, #8B5CF6, #7C3AED);
    color: white;
}

.math-solver-modal-content {
    width: 90vw;
    max-width: 800px;
    height: 90vh;
    max-height: 90vh;
    display: flex;
    flex-direction: column;
}

.math-solver-modal-body {
    display: flex;
    flex-direction: column;
    gap: 16px;
    padding: 20px;
    overflow-y: auto;
    flex: 1;
}

.math-solver-input-section {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.math-solver-input-section label {
    font-weight: 600;
    color: var(--gray-700);
}

/* MathLive Input Container */
.math-input-container {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

#mathFieldInput {
    font-size: 22px;
    padding: 16px;
    border: 2px solid var(--gray-300);
    border-radius: var(--radius);
    background: white;
    min-height: 60px;
}

#mathFieldInput:focus-within {
    border-color: #8B5CF6;
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.15);
}

.math-input-help {
    display: flex;
    gap: 12px;
    font-size: 12px;
    color: var(--gray-500);
}

.math-input-help .help-tip {
    cursor: help;
    padding: 2px 6px;
    background: var(--gray-100);
    border-radius: 4px;
    font-family: 'Consolas', 'Monaco', monospace;
}

.math-input-help .help-tip:hover {
    background: var(--gray-200);
}

/* Text input as alternative */
.math-text-input {
    padding: 10px 12px;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius);
    font-size: 14px;
    font-family: var(--font);
    resize: none;
}

.math-text-input:focus {
    outline: none;
    border-color: #8B5CF6;
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.15);
}

.math-text-input::placeholder {
    color: var(--gray-400);
}

#mathProblemInput {
    padding: 12px;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius);
    font-size: 15px;
    font-family: 'Consolas', 'Monaco', monospace;
    resize: vertical;
    min-height: 100px;
}

#mathProblemInput:focus {
    outline: none;
    border-color: #8B5CF6;
    box-shadow: 0 0 0 3px rgba(139, 92, 246, 0.15);
}

#mathProblemInput::placeholder {
    color: var(--gray-400);
    font-family: var(--font);
}

#btnSolveMath {
    align-self: flex-start;
    background: linear-gradient(135deg, #8B5CF6, #7C3AED);
    padding: 10px 20px;
}

#btnSolveMath:hover {
    background: linear-gradient(135deg, #7C3AED, #6D28D9);
}

.math-solver-output-section {
    background: var(--gray-50);
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    padding: 20px;
    min-height: 300px;
    flex: 1;
    overflow-y: auto;
}

.math-solver-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 12px;
    padding: 40px 20px;
    text-align: center;
    color: var(--gray-500);
}

.math-solver-placeholder p {
    margin: 0;
}

.math-solver-loading {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 12px;
    padding: 40px;
}

.math-solver-loading .spinner {
    width: 32px;
    height: 32px;
    border: 3px solid var(--gray-200);
    border-top-color: #8B5CF6;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

.math-solver-solution {
    line-height: 1.7;
}

.math-solver-solution h4 {
    margin: 0 0 16px 0;
    color: #7C3AED;
    font-size: 16px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.math-solver-solution .step {
    margin-bottom: 16px;
    padding: 12px 16px;
    background: white;
    border-radius: var(--radius);
    border-left: 3px solid #8B5CF6;
}

.math-solver-solution .step-number {
    font-weight: 600;
    color: #7C3AED;
    margin-bottom: 4px;
}

.math-solver-solution .step-content {
    color: var(--gray-700);
}

.math-solver-solution .final-answer {
    margin-top: 20px;
    padding: 16px;
    background: linear-gradient(135deg, rgba(139, 92, 246, 0.1), rgba(124, 58, 237, 0.1));
    border-radius: var(--radius);
    border: 1px solid rgba(139, 92, 246, 0.3);
}

.math-solver-solution .final-answer h5 {
    margin: 0 0 8px 0;
    color: #7C3AED;
    font-size: 14px;
}

.math-solver-solution .final-answer p {
    margin: 0;
    font-size: 18px;
    font-weight: 600;
    color: var(--gray-800);
    font-family: 'Consolas', 'Monaco', monospace;
}

/* Math Solver Mode Toggle */
.math-solver-mode-toggle {
    display: flex;
    gap: 12px;
    margin-top: 4px;
}

.math-solver-mode-toggle .mode-option {
    flex: 1;
    cursor: pointer;
}

.math-solver-mode-toggle .mode-option input {
    display: none;
}

.math-solver-mode-toggle .mode-label {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 14px;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius);
    background: white;
    color: var(--gray-600);
    font-size: 14px;
    font-weight: 500;
    transition: all 0.2s;
}

.math-solver-mode-toggle .mode-option input:checked + .mode-label {
    border-color: #8B5CF6;
    background: rgba(139, 92, 246, 0.08);
    color: #7C3AED;
}

.math-solver-mode-toggle .mode-label:hover {
    border-color: #8B5CF6;
}

.math-solver-mode-toggle .mode-label svg {
    flex-shrink: 0;
}

/* Math Solver Action Buttons */
.math-solver-actions {
    display: flex;
    gap: 10px;
    margin-top: 4px;
}

#btnClearMath {
    background: var(--gray-100);
    color: var(--gray-700);
    border: 1px solid var(--gray-300);
}

#btnClearMath:hover {
    background: var(--gray-200);
}

/* Math Test Mode Styles */
.math-test-container {
    padding: 8px;
}

.math-test-progress {
    margin-bottom: 20px;
}

.math-test-progress .progress-bar {
    height: 8px;
    background: var(--gray-200);
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 8px;
}

.math-test-progress .progress-fill {
    height: 100%;
    background: linear-gradient(135deg, #8B5CF6, #7C3AED);
    border-radius: 4px;
    transition: width 0.3s ease;
}

.math-test-progress .progress-text {
    font-size: 13px;
    color: var(--gray-500);
    font-weight: 500;
}

.math-test-question {
    margin-bottom: 20px;
}

.math-test-question h4 {
    margin: 0 0 8px 0;
    font-size: 16px;
    color: var(--gray-800);
    line-height: 1.5;
}

.math-test-question .test-context {
    margin: 0;
    padding: 10px 14px;
    background: var(--gray-100);
    border-radius: var(--radius);
    font-family: 'Consolas', 'Monaco', monospace;
    font-size: 14px;
    color: var(--gray-700);
}

.math-test-options {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.math-test-option {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 14px 16px;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius);
    background: white;
    cursor: pointer;
    transition: all 0.2s;
    text-align: left;
}

.math-test-option:hover:not(:disabled) {
    border-color: #8B5CF6;
    background: rgba(139, 92, 246, 0.05);
}

.math-test-option:disabled {
    cursor: default;
}

.math-test-option .option-letter {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    background: var(--gray-100);
    font-weight: 600;
    font-size: 13px;
    color: var(--gray-600);
    flex-shrink: 0;
}

.math-test-option .option-text {
    font-size: 14px;
    color: var(--gray-700);
    font-family: 'Consolas', 'Monaco', monospace;
}

.math-test-option.correct {
    border-color: #10B981;
    background: rgba(16, 185, 129, 0.08);
}

.math-test-option.correct .option-letter {
    background: #10B981;
    color: white;
}

.math-test-option.selected-correct {
    border-color: #10B981;
    background: rgba(16, 185, 129, 0.15);
}

.math-test-option.selected-wrong {
    border-color: #EF4444;
    background: rgba(239, 68, 68, 0.08);
}

.math-test-option.selected-wrong .option-letter {
    background: #EF4444;
    color: white;
}

/* Test Feedback */
.math-test-feedback {
    margin-top: 16px;
    padding: 14px 16px;
    border-radius: var(--radius);
    display: flex;
    align-items: flex-start;
    gap: 12px;
}

.math-test-feedback.correct {
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid rgba(16, 185, 129, 0.3);
    color: #059669;
    align-items: center;
}

.math-test-feedback.correct svg {
    color: #10B981;
}

.math-test-feedback.correct span {
    font-weight: 600;
    font-size: 15px;
}

.math-test-feedback.wrong {
    background: rgba(239, 68, 68, 0.08);
    border: 1px solid rgba(239, 68, 68, 0.2);
    flex-direction: column;
    gap: 8px;
}

.math-test-feedback.wrong .feedback-header {
    display: flex;
    align-items: center;
    gap: 8px;
    color: #DC2626;
    font-weight: 600;
}

.math-test-feedback.wrong .feedback-header svg {
    color: #EF4444;
}

.math-test-feedback.wrong .feedback-explanation {
    color: var(--gray-700);
    font-size: 14px;
    line-height: 1.6;
}

.math-test-feedback.wrong .feedback-explanation strong {
    color: #059669;
    font-family: 'Consolas', 'Monaco', monospace;
}

.math-test-feedback.wrong .feedback-explanation p {
    margin: 8px 0 0 0;
}

/* Continue Button */
.math-test-continue {
    margin-top: 20px;
    width: 100%;
    justify-content: center;
    display: flex;
    align-items: center;
    gap: 8px;
}

/* Test Complete Screen */
.math-test-complete {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 40px 20px;
    text-align: center;
}

.math-test-complete svg {
    color: #10B981;
    margin-bottom: 16px;
}

.math-test-complete h3 {
    margin: 0 0 8px 0;
    font-size: 20px;
    color: var(--gray-800);
}

.math-test-complete p {
    margin: 0 0 24px 0;
    color: var(--gray-600);
}

.test-complete-actions {
    display: flex;
    gap: 12px;
}

/* ============================================================
   Grammar Error Hunt Modal Styles
   ============================================================ */

/* Make tools modal draggable */
.tools-modal-content,
.grammar-hunt-modal-content {
    cursor: default;
}

.tools-modal-content .modal-header,
.grammar-hunt-header {
    cursor: move;
    user-select: none;
}

.grammar-hunt-modal-content {
    width: 800px;
    max-width: 95vw;
    max-height: 90vh;
    display: flex;
    flex-direction: column;
}

.grammar-hunt-modal-body {
    padding: 20px;
    overflow-y: auto;
    flex: 1;
}

.grammar-hunt-intro {
    text-align: center;
    color: var(--gray-600);
    margin-bottom: 20px;
}

.grammar-hunt-grade-select {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    margin-bottom: 24px;
}

.grammar-hunt-grade-select label {
    font-weight: 600;
    color: var(--gray-700);
}

.grammar-hunt-grade-select select {
    padding: 8px 16px;
    border: 1px solid var(--gray-300);
    border-radius: var(--radius);
    font-size: 14px;
    background: white;
}

.grammar-category-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 12px;
    margin-bottom: 24px;
}

@media (max-width: 768px) {
    .grammar-category-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 480px) {
    .grammar-category-grid {
        grid-template-columns: 1fr;
    }
}

.grammar-category-card {
    padding: 16px;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius);
    cursor: pointer;
    transition: all 0.2s;
    text-align: center;
}

.grammar-category-card:hover {
    border-color: #F59E0B;
    background: rgba(245, 158, 11, 0.05);
}

.grammar-category-card.selected {
    border-color: #F59E0B;
    background: rgba(245, 158, 11, 0.1);
    box-shadow: 0 0 0 3px rgba(245, 158, 11, 0.2);
}

.grammar-category-card .category-icon {
    font-size: 28px;
    margin-bottom: 8px;
}

.grammar-category-card h4 {
    margin: 0 0 6px 0;
    font-size: 14px;
    font-weight: 600;
    color: var(--gray-800);
}

.grammar-category-card p {
    margin: 0;
    font-size: 12px;
    color: var(--gray-500);
    line-height: 1.4;
}

#btnStartGrammarHunt {
    display: block;
    width: 100%;
    max-width: 400px;
    margin: 0 auto;
    padding: 14px 24px;
    font-size: 16px;
}

#btnStartGrammarHunt:disabled {
    background: var(--gray-300);
    cursor: not-allowed;
}

/* Game Area Styles */
.grammar-hunt-scoreboard {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 16px;
    background: linear-gradient(135deg, #F59E0B, #D97706);
    border-radius: var(--radius);
    margin-bottom: 16px;
    color: white;
}

.score-item {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.score-label {
    font-size: 11px;
    text-transform: uppercase;
    opacity: 0.9;
}

.score-value {
    font-size: 20px;
    font-weight: 700;
}

.category-badge {
    background: rgba(255, 255, 255, 0.2);
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 13px;
    font-weight: 600;
}

.grammar-hunt-instructions {
    text-align: center;
    padding: 12px;
    background: #FEF3C7;
    border-radius: var(--radius);
    margin-bottom: 16px;
    font-size: 14px;
    color: #92400E;
}

.grammar-hunt-text-container {
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    padding: 24px;
    min-height: 200px;
    margin-bottom: 16px;
}

.grammar-hunt-text {
    font-size: 16px;
    line-height: 2;
    color: var(--gray-800);
}

.grammar-hunt-text .grammar-word {
    cursor: pointer;
    padding: 2px 0;
    border-radius: 3px;
    transition: all 0.15s;
}

.grammar-hunt-text .grammar-word:hover {
    background: rgba(245, 158, 11, 0.2);
}

.grammar-hunt-text .grammar-word.error-word {
    /* Hidden initially - error words look normal */
}

.grammar-hunt-text .grammar-word.found {
    background: #D1FAE5;
    color: #065F46;
    text-decoration: line-through;
    text-decoration-color: #10B981;
    pointer-events: none;
}

.grammar-hunt-text .grammar-word.wrong-click {
    background: #FEE2E2;
    animation: wrongShake 0.3s ease;
    pointer-events: none;
}

.grammar-hunt-text .grammar-word.revealed {
    background: #FEF3C7;
    color: #92400E;
    border-bottom: 2px dashed #F59E0B;
    pointer-events: none;
}

@keyframes wrongShake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-4px); }
    75% { transform: translateX(4px); }
}

.grammar-hunt-loading {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 40px;
    color: var(--gray-500);
}

.grammar-hunt-loading .loading-spinner {
    width: 40px;
    height: 40px;
    border: 3px solid var(--gray-200);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 16px;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.grammar-hunt-error {
    text-align: center;
    padding: 40px;
    color: #DC2626;
}

.grammar-hunt-error .error-details {
    font-size: 13px;
    color: var(--gray-500);
    margin-top: 8px;
}

.grammar-hunt-feedback {
    padding: 16px;
    border-radius: var(--radius);
    margin-bottom: 16px;
    display: flex;
    align-items: center;
    gap: 12px;
}

.grammar-hunt-feedback .feedback-icon {
    font-size: 20px;
    font-weight: bold;
}

.grammar-hunt-feedback .feedback-text {
    flex: 1;
}

.grammar-hunt-feedback .feedback-hint {
    display: block;
    font-size: 13px;
    opacity: 0.8;
    margin-top: 4px;
}

.grammar-hunt-feedback.feedback-correct {
    background: #D1FAE5;
    border: 1px solid #10B981;
    color: #065F46;
}

.grammar-hunt-feedback.feedback-wrong {
    background: #FEE2E2;
    border: 1px solid #EF4444;
    color: #991B1B;
}

.grammar-hunt-actions {
    display: flex;
    justify-content: center;
    gap: 12px;
}

/* Results Area */
.grammar-hunt-results {
    padding: 20px;
}

.results-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--gray-200);
}

.results-header h4 {
    margin: 0;
    font-size: 18px;
}

.final-score {
    font-size: 24px;
    font-weight: 700;
    color: #F59E0B;
}

.results-explanation {
    margin-bottom: 24px;
}

.results-explanation h5 {
    margin: 0 0 16px 0;
    font-size: 14px;
    font-weight: 600;
    color: var(--gray-700);
}

.result-item {
    padding: 16px;
    background: var(--gray-50);
    border-radius: var(--radius);
    margin-bottom: 12px;
    border-left: 4px solid var(--gray-300);
}

.result-item.found {
    border-left-color: #10B981;
}

.result-item.missed {
    border-left-color: #EF4444;
}

.result-item .result-status {
    font-size: 12px;
    font-weight: 600;
    margin-bottom: 8px;
}

.result-item.found .result-status {
    color: #065F46;
}

.result-item.missed .result-status {
    color: #DC2626;
}

.result-item .result-error {
    margin-bottom: 8px;
}

.result-item .error-text {
    font-family: 'Consolas', 'Monaco', monospace;
    background: #FEE2E2;
    padding: 2px 6px;
    border-radius: 3px;
    color: #DC2626;
    text-decoration: line-through;
}

.result-item .correction {
    font-family: 'Consolas', 'Monaco', monospace;
    background: #D1FAE5;
    padding: 2px 6px;
    border-radius: 3px;
    color: #065F46;
    margin-left: 8px;
}

.result-item .result-category {
    font-size: 12px;
    font-weight: 500;
    color: var(--primary);
    margin-bottom: 8px;
}

.result-item .result-explanation {
    font-size: 13px;
    color: var(--gray-600);
    line-height: 1.5;
}

.results-actions {
    display: flex;
    justify-content: center;
    gap: 12px;
}

/* ============================================================
   GeoConquest - Risk-style Geography Game
   ============================================================ */
.geoconquest-modal-content {
    width: 95vw;
    max-width: 1100px;
    height: 90vh;
    max-height: 800px;
    display: flex;
    flex-direction: column;
}

.geoconquest-header {
    background: linear-gradient(135deg, #059669, #047857);
    color: white;
    padding: 16px 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-radius: var(--radius) var(--radius) 0 0;
}

.geoconquest-header h3 {
    margin: 0;
    font-size: 20px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.geoconquest-header h3::before {
    content: '🌍';
}

/* Setup Screen */
.geoconquest-setup {
    padding: 24px;
    overflow-y: auto;
    flex: 1;
}

.gc-intro {
    text-align: center;
    margin-bottom: 24px;
}

.gc-intro h4 {
    color: #059669;
    margin: 0 0 8px 0;
    font-size: 18px;
}

.gc-intro p {
    color: var(--gray-600);
    margin: 0;
}

.gc-region-select,
.gc-difficulty-select,
.gc-rules {
    margin-bottom: 24px;
    text-align: center;
}

.gc-region-select h5,
.gc-difficulty-select h5,
.gc-rules h5 {
    margin: 0 0 12px 0;
    color: var(--gray-800);
    font-size: 15px;
}

.gc-region-select p {
    color: var(--gray-600);
    margin: 0 0 12px 0;
}

/* Troop Legend */
.gc-legend {
    display: flex;
    justify-content: center;
    gap: 24px;
    margin-top: 12px;
}

.gc-legend-item {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 14px;
    color: var(--gray-700);
}

.gc-legend-circle {
    display: inline-block;
    width: 14px;
    height: 14px;
    border-radius: 50%;
    border: 2px solid;
}

.gc-legend-circle.player {
    background: #3498db;
    border-color: #2980b9;
}

.gc-legend-circle.ai {
    background: #e74c3c;
    border-color: #c0392b;
}

.gc-difficulty-buttons {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
}

.gc-difficulty-btn {
    flex: 1;
    min-width: 140px;
    padding: 16px;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius);
    background: white;
    cursor: pointer;
    transition: all 0.2s;
    text-align: center;
}

.gc-difficulty-btn:hover {
    border-color: #059669;
}

.gc-difficulty-btn.selected {
    border-color: #059669;
    background: rgba(5, 150, 105, 0.08);
}

.gc-difficulty-btn .diff-name {
    display: block;
    font-weight: 600;
    font-size: 16px;
    color: var(--gray-800);
    margin-bottom: 4px;
}

.gc-difficulty-btn .diff-desc {
    display: block;
    font-size: 12px;
    color: var(--gray-500);
}

/* Theater selection buttons */
.gc-theater-select {
    margin-bottom: 20px;
}

.gc-theater-select h5 {
    margin-bottom: 12px;
    color: var(--gray-700);
    font-size: 14px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.gc-theater-buttons {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
}

.gc-theater-btn {
    padding: 16px;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius);
    background: white;
    cursor: pointer;
    transition: all 0.2s;
    text-align: center;
}

.gc-theater-btn:hover {
    border-color: #059669;
    transform: translateY(-2px);
}

.gc-theater-btn.selected {
    border-color: #059669;
    background: rgba(5, 150, 105, 0.08);
    box-shadow: 0 2px 8px rgba(5, 150, 105, 0.2);
}

.gc-theater-btn .theater-name {
    display: block;
    font-weight: 600;
    font-size: 18px;
    color: var(--gray-800);
    margin-bottom: 4px;
}

.gc-theater-btn .theater-desc {
    display: block;
    font-size: 12px;
    color: var(--gray-500);
}

.gc-region-info {
    margin-bottom: 16px;
    padding: 12px;
    background: var(--gray-50);
    border-radius: var(--radius);
}

.gc-rules ul {
    margin: 0;
    padding-left: 20px;
    color: var(--gray-600);
    font-size: 14px;
    line-height: 1.8;
}

.gc-rules ul li strong {
    color: #059669;
}

.gc-start-btn {
    width: 100%;
    padding: 16px;
    font-size: 18px;
    background: linear-gradient(135deg, #059669, #047857);
    border: none;
    color: white;
    border-radius: var(--radius);
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s;
}

.gc-start-btn:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(5, 150, 105, 0.3);
}

.gc-start-btn:disabled {
    background: linear-gradient(135deg, #6b7280, #4b5563);
    cursor: not-allowed;
    opacity: 0.7;
}

/* Game Screen */
.geoconquest-game {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.gc-game-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 16px;
    background: var(--gray-50);
    border-bottom: 1px solid var(--gray-200);
    flex-wrap: wrap;
    gap: 12px;
}

.gc-phase-indicator {
    font-weight: 600;
    color: #059669;
    font-size: 15px;
}

.gc-reinforcements {
    background: #059669;
    color: white;
    padding: 6px 12px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: 500;
}

.gc-stats {
    display: flex;
    gap: 16px;
    font-size: 13px;
}

.gc-stat {
    display: flex;
    gap: 6px;
}

.gc-stat .stat-label {
    color: var(--gray-500);
}

.gc-stat .stat-value {
    font-weight: 600;
    color: var(--gray-800);
}

.gc-stat .stat-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    display: inline-block;
    margin-right: 4px;
}

.gc-stat .stat-dot.player {
    background-color: #3498db;
    box-shadow: 0 0 3px rgba(52, 152, 219, 0.5);
}

.gc-stat .stat-dot.ai {
    background-color: #e74c3c;
    box-shadow: 0 0 3px rgba(231, 76, 60, 0.5);
}

.gc-toggle-btn {
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 6px 12px;
    border-radius: 6px;
    font-size: 12px;
    cursor: pointer;
    transition: background 0.2s;
}

.gc-toggle-btn:hover {
    background: var(--primary-hover);
}

/* Map Container */
.gc-map-container {
    flex: 1;
    position: relative;
    min-height: 300px;
}

.gc-map {
    width: 100%;
    height: 100%;
    cursor: pointer;
}

/* Leaflet container cursor - must target all panes */
#geoconquestMap,
#geoconquestMap .leaflet-container,
#geoconquestMap .leaflet-pane,
#geoconquestMap .leaflet-tile-pane,
#geoconquestMap .leaflet-overlay-pane,
#geoconquestMap .leaflet-map-pane,
#geoconquestMap .leaflet-tile,
#geoconquestMap .leaflet-interactive {
    cursor: pointer !important;
}

.gc-message {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    background: rgba(0, 0, 0, 0.8);
    color: white;
    padding: 12px 24px;
    border-radius: 8px;
    font-size: 14px;
    z-index: 1000;
    max-width: 80%;
    text-align: center;
}

.gc-loading {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: rgba(255, 255, 255, 0.95);
    padding: 24px 32px;
    border-radius: var(--radius);
    display: flex;
    align-items: center;
    gap: 12px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
    z-index: 1001;
}

.gc-spinner {
    width: 24px;
    height: 24px;
    border: 3px solid var(--gray-200);
    border-top-color: #059669;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

/* Territory Labels - Hidden by default, show on hover */
.gc-territory-label {
    background: transparent !important;
    border: none !important;
    pointer-events: none;
}

.gc-label-hidden {
    opacity: 0;
    transition: opacity 0.2s ease;
}

.gc-label-visible {
    opacity: 1;
    transition: opacity 0.2s ease;
}

.gc-label-content {
    background: rgba(255, 255, 255, 0.95);
    padding: 6px 12px;
    border-radius: 6px;
    text-align: center;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
    white-space: nowrap;
}

.gc-territory-name {
    display: block;
    font-size: 13px;
    font-weight: 600;
    color: var(--gray-800);
}

/* Troop Circle Markers */
.gc-troop-marker {
    cursor: pointer;
    transition: transform 0.1s ease;
}

.gc-troop-marker:hover {
    transform: scale(1.2);
}

/* Panels */
.gc-panel {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: white;
    padding: 24px;
    border-radius: var(--radius-lg);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.2);
    z-index: 1002;
    max-width: 90%;
    width: 400px;
}

.gc-panel h4 {
    margin: 0 0 16px 0;
    color: var(--gray-800);
    text-align: center;
}

.gc-panel p {
    text-align: center;
    color: var(--gray-600);
    margin: 0 0 16px 0;
}

/* Challenge Buttons */
.gc-challenge-buttons,
.gc-defense-buttons {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.gc-challenge-btn,
.gc-defense-btn {
    padding: 16px;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius);
    background: white;
    cursor: pointer;
    transition: all 0.2s;
    text-align: left;
}

.gc-challenge-btn:hover,
.gc-defense-btn:hover {
    transform: translateX(4px);
}

.gc-challenge-bold:hover,
.gc-defense-allin:hover {
    border-color: #EF4444;
    background: rgba(239, 68, 68, 0.05);
}

.gc-challenge-standard:hover,
.gc-defense-balanced:hover {
    border-color: #F59E0B;
    background: rgba(245, 158, 11, 0.05);
}

.gc-challenge-cautious:hover,
.gc-defense-safe:hover {
    border-color: #10B981;
    background: rgba(16, 185, 129, 0.05);
}

.gc-challenge-btn .challenge-name,
.gc-defense-btn .defense-name {
    display: block;
    font-weight: 700;
    font-size: 16px;
    margin-bottom: 4px;
}

.gc-challenge-bold .challenge-name,
.gc-defense-allin .defense-name {
    color: #DC2626;
}

.gc-challenge-standard .challenge-name,
.gc-defense-balanced .defense-name {
    color: #D97706;
}

.gc-challenge-cautious .challenge-name,
.gc-defense-safe .defense-name {
    color: #059669;
}

.gc-challenge-btn .challenge-desc,
.gc-challenge-btn .challenge-effect,
.gc-defense-btn .defense-desc,
.gc-defense-btn .defense-effect {
    display: block;
    font-size: 12px;
    color: var(--gray-500);
}

/* Question Panel */
.gc-question-text {
    font-size: 16px;
    line-height: 1.6;
    color: var(--gray-800);
    margin-bottom: 20px;
    padding: 16px;
    background: var(--gray-50);
    border-radius: var(--radius);
}

.gc-answer-options {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.gc-answer-btn {
    padding: 14px 16px;
    border: 2px solid var(--gray-200);
    border-radius: var(--radius);
    background: white;
    cursor: pointer;
    text-align: left;
    font-size: 14px;
    transition: all 0.2s;
    display: flex;
    align-items: center;
    gap: 12px;
}

.gc-answer-btn:hover {
    border-color: #059669;
    background: rgba(5, 150, 105, 0.05);
}

.gc-answer-btn .answer-key {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    background: var(--gray-100);
    border-radius: 50%;
    font-weight: 600;
    color: var(--gray-600);
    flex-shrink: 0;
}

.gc-answer-btn:hover .answer-key {
    background: #059669;
    color: white;
}

/* Battle Result */
.gc-battle-result {
    display: flex;
    gap: 16px;
    align-items: flex-start;
    padding: 16px;
    border-radius: var(--radius);
    margin-bottom: 16px;
}

.gc-battle-result.result-correct {
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid #10B981;
}

.gc-battle-result.result-wrong {
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid #EF4444;
}

.gc-battle-result .battle-icon {
    font-size: 32px;
}

.gc-battle-result .battle-answer {
    font-weight: 700;
    font-size: 18px;
    margin-bottom: 8px;
}

.result-correct .battle-answer {
    color: #059669;
}

.result-wrong .battle-answer {
    color: #DC2626;
}

.gc-battle-result .battle-rolls,
.gc-battle-result .battle-losses {
    font-size: 13px;
    color: var(--gray-600);
    margin-bottom: 4px;
}

.gc-battle-result .battle-conquest,
.gc-battle-result .battle-lost {
    font-size: 16px;
    font-weight: 600;
    margin-top: 8px;
}

.battle-conquest {
    color: #059669;
}

.battle-lost {
    color: #DC2626;
}

.battle-message {
    text-align: center;
    font-size: 14px;
    color: var(--gray-600);
}

/* AI Actions */
.gc-ai-actions {
    background: rgba(239, 68, 68, 0.05);
    border: 1px solid #EF4444;
}

.ai-action {
    padding: 8px 0;
    font-size: 14px;
    color: var(--gray-700);
    border-bottom: 1px solid rgba(239, 68, 68, 0.2);
}

.ai-action:last-child {
    border-bottom: none;
}

/* Victory/Defeat */
.gc-victory,
.gc-defeat {
    text-align: center;
    padding: 24px;
}

.gc-victory h2 {
    color: #059669;
    margin: 0 0 12px 0;
}

.gc-defeat h2 {
    color: #DC2626;
    margin: 0 0 12px 0;
}

.gc-victory p,
.gc-defeat p {
    margin-bottom: 24px;
}

/* Territory Selection Indicators */
.gc-selection-pulse {
    animation: gc-pulse 1.5s ease-in-out infinite;
}

.gc-target-pulse {
    animation: gc-target-pulse 1s ease-in-out infinite;
}

@keyframes gc-pulse {
    0%, 100% { stroke-opacity: 0.8; stroke-width: 3; }
    50% { stroke-opacity: 0.4; stroke-width: 5; }
}

@keyframes gc-target-pulse {
    0%, 100% { stroke-opacity: 0.8; }
    50% { stroke-opacity: 0.3; }
}

/* Pool labels */
.gc-pool-label {
    background: transparent !important;
    border: none !important;
    box-shadow: none !important;
}

/* Action Buttons */
.gc-action-buttons {
    padding: 12px 16px;
    background: var(--gray-50);
    border-top: 1px solid var(--gray-200);
}

.gc-button-group {
    display: flex;
    justify-content: center;
    gap: 12px;
}

.gc-btn {
    padding: 10px 20px;
    border-radius: var(--radius);
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
}

.gc-btn-primary {
    background: #059669;
    color: white;
    border: none;
}

.gc-btn-primary:hover {
    background: #047857;
}

/* Tool Card Icon */
.geoconquest-icon {
    background: linear-gradient(135deg, #059669, #047857);
}

/* Rules Brief */
.gc-rules-brief {
    text-align: center;
    padding: 16px;
    background: var(--gray-50);
    border-radius: var(--radius);
    margin-bottom: 20px;
}

.gc-rules-brief p {
    margin: 0 0 12px 0;
    color: var(--gray-700);
}

.gc-rules-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

/* Full Rules Panel */
.gc-rules-panel {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.6);
    z-index: 2000;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.gc-rules-content {
    background: white;
    border-radius: var(--radius-lg);
    max-width: 700px;
    max-height: 85vh;
    width: 100%;
    display: flex;
    flex-direction: column;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
}

.gc-rules-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 24px;
    border-bottom: 1px solid var(--gray-200);
    background: linear-gradient(135deg, #059669, #047857);
    border-radius: var(--radius-lg) var(--radius-lg) 0 0;
}

.gc-rules-header h3 {
    margin: 0;
    color: white;
    font-size: 20px;
}

.gc-rules-header .close-btn {
    background: rgba(255, 255, 255, 0.2);
    border: none;
    color: white;
    font-size: 24px;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.2s;
}

.gc-rules-header .close-btn:hover {
    background: rgba(255, 255, 255, 0.3);
}

.gc-rules-body {
    padding: 24px;
    overflow-y: auto;
    flex: 1;
}

.rules-section {
    margin-bottom: 28px;
}

.rules-section:last-child {
    margin-bottom: 0;
}

.rules-section h4 {
    color: #059669;
    margin: 0 0 12px 0;
    font-size: 18px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.rules-section h5 {
    color: var(--gray-700);
    margin: 16px 0 8px 0;
    font-size: 15px;
}

.rules-section p {
    color: var(--gray-600);
    line-height: 1.6;
    margin: 0 0 12px 0;
}

.rules-section ul,
.rules-section ol {
    margin: 0 0 12px 0;
    padding-left: 24px;
    color: var(--gray-600);
    line-height: 1.8;
}

.rules-section li {
    margin-bottom: 4px;
}

.rules-section li strong {
    color: var(--gray-800);
}

/* Rules Tables */
.rules-table {
    background: var(--gray-50);
    border-radius: var(--radius);
    overflow: hidden;
    margin: 12px 0;
}

.rules-row {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr 1.5fr;
    gap: 8px;
    padding: 10px 12px;
    font-size: 13px;
    border-bottom: 1px solid var(--gray-200);
}

.rules-row:last-child {
    border-bottom: none;
}

.rules-header-row {
    background: var(--gray-200);
    font-weight: 600;
    color: var(--gray-700);
}

.rules-row.rules-bold {
    border-left: 3px solid #EF4444;
}

.rules-row.rules-standard {
    border-left: 3px solid #F59E0B;
}

.rules-row.rules-cautious {
    border-left: 3px solid #10B981;
}

.rules-bold strong {
    color: #DC2626;
}

.rules-standard strong {
    color: #D97706;
}

.rules-cautious strong {
    color: #059669;
}

/* ============================================================
   Languages Screen - FSI Language Courses
   ============================================================ */
.languages-layout {
    display: flex;
    flex: 1;
    height: 100%;
    overflow: hidden;
}

.languages-left {
    width: 280px;
    min-width: 200px;
    max-width: 400px;
    background: var(--gray-50);
    border-right: 1px solid var(--gray-200);
    display: flex;
    flex-direction: column;
    transition: width 0.2s ease;
}

.languages-left.collapsed {
    width: 48px;
    min-width: 48px;
}

.languages-left.collapsed .languages-nav-content {
    display: none;
}

.languages-left.collapsed .languages-nav-header h3 {
    display: none;
}

.languages-nav-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 16px;
    background: linear-gradient(135deg, #6366F1, #8B5CF6);
    color: white;
}

.languages-nav-header h3 {
    margin: 0;
    font-size: 16px;
    font-weight: 600;
    white-space: nowrap;
}

.languages-collapse-btn {
    width: 24px;
    height: 24px;
    border: none;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 4px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    transition: background 0.15s;
    flex-shrink: 0;
}

.languages-collapse-btn:hover {
    background: rgba(255, 255, 255, 0.3);
}

.languages-left.collapsed .languages-collapse-btn .collapse-icon {
    transform: rotate(180deg);
}

.languages-nav-content {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
}

.languages-selector,
.languages-course-selector {
    margin-bottom: 16px;
}

.languages-selector label,
.languages-course-selector label {
    display: block;
    font-size: 12px;
    font-weight: 600;
    color: var(--gray-500);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 6px;
}

.languages-selector select,
.languages-course-selector select {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    background: white;
    cursor: pointer;
}

.languages-selector select:focus,
.languages-course-selector select:focus {
    outline: none;
    border-color: #6366F1;
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
}

.languages-unit-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.languages-unit-item {
    padding: 10px 12px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.15s;
}

.languages-unit-item:hover {
    border-color: #6366F1;
    background: #F5F3FF;
}

.languages-unit-item.active {
    background: #6366F1;
    border-color: #6366F1;
    color: white;
}

.languages-unit-item .unit-number {
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    opacity: 0.7;
    margin-bottom: 2px;
}

.languages-unit-item .unit-title {
    font-size: 13px;
    font-weight: 500;
}

.languages-resizer {
    width: 4px;
    background: var(--gray-200);
    cursor: col-resize;
    transition: background 0.15s;
}

.languages-resizer:hover,
.languages-resizer.resizing {
    background: #6366F1;
}

.languages-right {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: white;
}

.languages-lesson-placeholder {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.languages-lesson-placeholder .placeholder-content {
    text-align: center;
    color: var(--gray-500);
}

.languages-lesson-placeholder .placeholder-content p {
    margin: 12px 0 4px 0;
    font-size: 16px;
}

.languages-lesson-placeholder .placeholder-content .text-muted {
    font-size: 13px;
    margin: 4px 0 0 0;
}

.languages-lesson-content {
    flex: 1;
    overflow-y: auto;
    padding: 24px;
}

.languages-lesson-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 24px;
    padding-bottom: 16px;
    border-bottom: 1px solid var(--gray-200);
}

.languages-lesson-header h2 {
    margin: 0;
    font-size: 22px;
    color: var(--gray-800);
}

.languages-lesson-actions {
    display: flex;
    gap: 8px;
}

.languages-lesson-actions .btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.languages-audio-section {
    margin-bottom: 32px;
}

.languages-audio-section h4,
.languages-ai-section h4 {
    margin: 0 0 12px 0;
    font-size: 14px;
    font-weight: 600;
    color: var(--gray-700);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.languages-audio-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.languages-audio-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    background: var(--gray-50);
    border: 1px solid var(--gray-200);
    border-radius: 8px;
}

.languages-audio-item .audio-info {
    flex: 1;
    min-width: 0;
}

.languages-audio-item .audio-title {
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-800);
    margin: 0 0 2px 0;
}

.languages-audio-item .audio-duration {
    font-size: 12px;
    color: var(--gray-500);
}

.languages-audio-item audio {
    flex-shrink: 0;
    height: 36px;
}

.languages-audio-item .audio-play-btn {
    width: 40px;
    height: 40px;
    border: none;
    background: #6366F1;
    color: white;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.15s, transform 0.1s;
    flex-shrink: 0;
}

.languages-audio-item .audio-play-btn:hover {
    background: #4F46E5;
    transform: scale(1.05);
}

.languages-audio-item .audio-play-btn.playing {
    background: #EF4444;
}

.languages-audio-item .audio-rewind-btn {
    width: 32px;
    height: 32px;
    border: none;
    background: #9CA3AF;
    color: white;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.15s, transform 0.1s;
    flex-shrink: 0;
    margin-left: 4px;
}

.languages-audio-item .audio-rewind-btn:hover {
    background: #6B7280;
    transform: scale(1.05);
}

.languages-audio-item.active {
    background: #EEF2FF;
    border-color: #6366F1;
}

.languages-ai-section {
    padding: 20px;
    background: linear-gradient(135deg, #F5F3FF, #EEF2FF);
    border-radius: 12px;
    border: 1px solid #E0E7FF;
}

.languages-ai-section p {
    margin: 0 0 16px 0;
    font-size: 14px;
}

.languages-ai-section .btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

/* PDF hint text */
.languages-pdf-hint {
    font-size: 13px;
    margin: 0 0 12px 0;
}

/* Transcript Section */
.languages-transcript-section {
    margin-bottom: 32px;
}

.languages-transcript-section h4 {
    margin: 0 0 12px 0;
    font-size: 14px;
    font-weight: 600;
    color: var(--gray-700);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
}

.transcript-controls {
    display: flex;
    align-items: center;
    gap: 12px;
}

.transcript-toggle {
    display: flex;
    align-items: center;
    gap: 6px;
    cursor: pointer;
    font-size: 12px;
    text-transform: none;
    font-weight: normal;
    color: var(--gray-600);
}

.transcript-toggle input[type="checkbox"] {
    width: 16px;
    height: 16px;
    cursor: pointer;
}

.languages-transcript-container {
    background: #fff;
    border: 1px solid var(--gray-300);
    border-radius: 8px;
    min-height: 200px;
    max-height: 400px;
    overflow-y: auto;
    padding: 16px;
}

.transcript-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 150px;
    text-align: center;
    color: var(--gray-500);
}

.transcript-loading {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-height: 150px;
    color: var(--gray-600);
}

.transcript-loading::before {
    content: '';
    width: 24px;
    height: 24px;
    border: 3px solid var(--gray-300);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    margin-bottom: 12px;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.transcript-content {
    line-height: 1.8;
}

.transcript-line {
    padding: 8px 12px;
    margin: 4px 0;
    border-radius: 6px;
    transition: background-color 0.2s;
}

.transcript-line:hover {
    background-color: var(--gray-100);
}

.transcript-line.active {
    background-color: #fff3cd;
    border-left: 3px solid #ffc107;
}

.transcript-original {
    font-size: 16px;
    color: var(--gray-900);
    font-weight: 500;
}

.transcript-translation {
    font-size: 14px;
    color: var(--gray-600);
    font-style: italic;
    margin-top: 4px;
    display: none;
}

.show-translation .transcript-translation {
    display: block;
}

.transcript-error {
    color: var(--danger-color);
    text-align: center;
    padding: 20px;
}

.transcript-not-available {
    text-align: center;
    padding: 30px 20px;
    color: var(--gray-600);
}

.transcript-not-available p {
    margin: 0 0 16px 0;
}

.transcript-not-available .btn {
    margin-top: 8px;
}

/* Real-time transcription status */
.transcript-status {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 16px;
    background: var(--gray-50);
    border-radius: 8px;
    color: var(--gray-600);
    font-size: 14px;
}

.status-indicator {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    flex-shrink: 0;
}

.status-indicator.listening {
    background: #10B981;
    animation: pulse-green 1.5s ease-in-out infinite;
}

.status-indicator.stopped {
    background: var(--gray-400);
}

@keyframes pulse-green {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.5; transform: scale(1.2); }
}

.translation-loading {
    color: var(--gray-400);
    font-style: italic;
}

.translation-error {
    color: var(--danger-color);
    font-size: 12px;
}

/* PDF Viewer Section */
.languages-pdf-section {
    margin-bottom: 32px;
}

.pdf-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 150px;
    text-align: center;
    color: var(--gray-500);
}

.languages-pdf-section h4 {
    margin: 0 0 12px 0;
    font-size: 14px;
    font-weight: 600;
    color: var(--gray-700);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.languages-pdf-section h4 .btn {
    padding: 4px 8px;
    font-size: 12px;
}

.languages-pdf-container {
    background: #f8f9fa;
    border: 1px solid var(--gray-300);
    border-radius: 8px;
    overflow: hidden;
    height: 500px;
}

.languages-pdf-container iframe {
    width: 100%;
    height: 100%;
    border: none;
}

.languages-pdf-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    padding: 40px 20px;
    text-align: center;
    color: var(--gray-600);
}

.languages-pdf-placeholder svg {
    color: var(--gray-400);
    margin-bottom: 16px;
}

.languages-pdf-placeholder p {
    margin: 0 0 8px 0;
}

.languages-pdf-placeholder p strong {
    font-size: 18px;
    color: var(--gray-800);
}

.languages-pdf-placeholder .btn {
    margin-top: 16px;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

/* Language flag icons (optional styling) */
.language-flag {
    width: 20px;
    height: 14px;
    border-radius: 2px;
    margin-right: 8px;
}

/* ============================================================
   History Screen - OER Project Integration
   ============================================================ */
.history-layout {
    display: flex;
    flex: 1;
    height: 100%;
    overflow: hidden;
}

.history-left {
    width: 280px;
    min-width: 200px;
    max-width: 500px;
    background: var(--gray-50);
    border-right: 1px solid var(--gray-200);
    display: flex;
    flex-direction: column;
    transition: width 0.2s ease;
}

.history-left.collapsed {
    width: 48px;
    min-width: 48px;
}

.history-left.collapsed .history-nav-content {
    display: none;
}

.history-left.collapsed .history-nav-header h3 {
    display: none;
}

.history-nav-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 16px;
    background: linear-gradient(135deg, #B45309, #D97706);
    color: white;
}

.history-nav-header h3 {
    margin: 0;
    font-size: 16px;
    font-weight: 600;
    white-space: nowrap;
}

.history-collapse-btn {
    width: 24px;
    height: 24px;
    border: none;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 4px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    transition: background 0.15s;
    flex-shrink: 0;
}

.history-collapse-btn:hover {
    background: rgba(255, 255, 255, 0.3);
}

.history-left.collapsed .history-collapse-btn .collapse-icon {
    transform: rotate(180deg);
}

.history-nav-content {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
}

/* History Source Toggle (OpenStax / MIT) */
.history-source-toggle {
    display: flex;
    gap: 16px;
    margin-bottom: 16px;
    padding: 12px;
    background: var(--gray-50);
    border-radius: var(--radius);
    border: 1px solid var(--gray-200);
}

.history-source-toggle .history-radio-label {
    display: flex !important;
    align-items: center;
    gap: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-700);
    margin-bottom: 0 !important;
}

.history-source-toggle .history-radio-label input[type="radio"] {
    width: 16px;
    height: 16px;
    cursor: pointer;
    accent-color: #D97706;
    display: inline-block !important;
}

.history-source-toggle .history-radio-label:hover {
    color: #D97706;
}

/* OpenStax Section */
.history-openstax-section {
    display: block;
}

/* MIT History Section */
.history-mit-section {
    display: block;
}

.history-mit-course-selector {
    margin-bottom: 16px;
}

.history-mit-course-selector select {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    background: white;
    cursor: pointer;
}

.history-mit-course-selector select:focus {
    outline: none;
    border-color: #D97706;
    box-shadow: 0 0 0 3px rgba(217, 119, 6, 0.15);
}

.history-mit-chapter-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.history-mit-chapter-item {
    display: flex;
    gap: 8px;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    background: white;
    padding: 10px 12px;
    cursor: pointer;
    transition: all 0.15s;
}

.history-mit-chapter-item:hover {
    background: var(--gray-50);
    border-color: #D97706;
}

.history-mit-chapter-item.active {
    background: #D97706;
    border-color: #D97706;
    color: white;
}

.history-mit-chapter-number {
    font-weight: 600;
    font-size: 13px;
    min-width: 24px;
}

.history-mit-chapter-title {
    font-size: 13px;
    flex: 1;
}

.history-mit-chapter-item.active .history-mit-chapter-number,
.history-mit-chapter-item.active .history-mit-chapter-title {
    color: white;
}

.history-selector,
.history-unit-selector {
    margin-bottom: 16px;
}

.history-selector label,
.history-unit-selector label {
    display: block;
    font-size: 12px;
    font-weight: 600;
    color: var(--gray-500);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 6px;
}

.history-selector select,
.history-unit-selector select {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    background: white;
    cursor: pointer;
}

.history-selector select:focus,
.history-unit-selector select:focus {
    outline: none;
    border-color: #D97706;
    box-shadow: 0 0 0 3px rgba(217, 119, 6, 0.15);
}

.history-lesson-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.history-lesson-item {
    padding: 10px 12px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.15s;
    display: flex;
    align-items: center;
    gap: 10px;
}

.history-lesson-item:hover {
    border-color: #D97706;
    background: #FFFBEB;
}

.history-lesson-item.active {
    background: #D97706;
    border-color: #D97706;
    color: white;
}

.history-lesson-item .lesson-number {
    font-size: 11px;
    font-weight: 700;
    background: var(--gray-200);
    padding: 2px 6px;
    border-radius: 4px;
    flex-shrink: 0;
}

.history-lesson-item.active .lesson-number {
    background: rgba(255, 255, 255, 0.2);
}

.history-lesson-item .lesson-name {
    font-size: 13px;
    font-weight: 500;
}

.history-resizer {
    width: 4px;
    background: var(--gray-200);
    cursor: col-resize;
    transition: background 0.15s;
}

.history-resizer:hover,
.history-resizer.resizing {
    background: #D97706;
}

.history-right {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: white;
}

.history-lesson-placeholder {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.history-lesson-placeholder .placeholder-content {
    text-align: center;
    color: var(--gray-500);
}

.history-lesson-placeholder .placeholder-content p {
    margin: 12px 0 4px 0;
    font-size: 16px;
}

.history-lesson-placeholder .placeholder-content .text-muted {
    font-size: 13px;
    margin: 4px 0 0 0;
}

.history-lesson-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.history-lesson-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 24px;
    border-bottom: 1px solid var(--gray-200);
    background: var(--gray-50);
}

.history-lesson-header h2 {
    margin: 0;
    font-size: 18px;
    color: var(--gray-800);
}

.history-lesson-actions {
    display: flex;
    gap: 8px;
}

.history-lesson-actions .btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

/* Study tool buttons in history/class lesson headers */
.history-lesson-actions.study-tools-header {
    justify-content: flex-end;
    gap: 8px;
}

.history-lesson-actions .btn-study-tool {
    display: flex !important;
    visibility: visible !important;
    opacity: 1 !important;
    align-items: center;
    justify-content: center;
    min-width: 46px;
    width: 46px;
    height: 46px;
    padding: 10px;
    border: none;
    border-radius: 8px;
    background: var(--bg-secondary, #f3f4f6);
    color: var(--text-secondary, #6b7280);
    cursor: pointer;
    transition: background 0.2s, color 0.2s, transform 0.1s;
    flex-shrink: 0;
}

.history-lesson-actions .btn-study-tool:hover {
    background: var(--primary-color, #2563eb) !important;
    color: white !important;
    opacity: 1 !important;
    visibility: visible !important;
    transform: scale(1.05);
}

.history-lesson-actions .btn-study-tool svg {
    width: 24px;
    height: 24px;
    flex-shrink: 0;
}

/* Study tool buttons - shared styles for all "More Classes" subjects */
.civics-lesson-actions.study-tools-header,
.economics-lesson-actions.study-tools-header,
.geography-lesson-actions.study-tools-header,
.sociology-lesson-actions.study-tools-header,
.arthistory-lesson-actions.study-tools-header,
.music-lesson-actions.study-tools-header,
.philosophy-lesson-actions.study-tools-header,
.linguistics-lesson-actions.study-tools-header,
.polisci-lesson-actions.study-tools-header,
.environment-lesson-actions.study-tools-header {
    justify-content: flex-end;
    gap: 8px;
}

.civics-lesson-actions .btn-study-tool,
.economics-lesson-actions .btn-study-tool,
.geography-lesson-actions .btn-study-tool,
.sociology-lesson-actions .btn-study-tool,
.arthistory-lesson-actions .btn-study-tool,
.music-lesson-actions .btn-study-tool,
.philosophy-lesson-actions .btn-study-tool,
.linguistics-lesson-actions .btn-study-tool,
.polisci-lesson-actions .btn-study-tool,
.environment-lesson-actions .btn-study-tool {
    display: flex !important;
    visibility: visible !important;
    opacity: 1 !important;
    align-items: center;
    justify-content: center;
    min-width: 46px;
    width: 46px;
    height: 46px;
    padding: 10px;
    border: none;
    border-radius: 8px;
    background: var(--bg-secondary, #f3f4f6);
    color: var(--text-secondary, #6b7280);
    cursor: pointer;
    transition: background 0.2s, color 0.2s, transform 0.1s;
    flex-shrink: 0;
}

.civics-lesson-actions .btn-study-tool:hover,
.economics-lesson-actions .btn-study-tool:hover,
.geography-lesson-actions .btn-study-tool:hover,
.sociology-lesson-actions .btn-study-tool:hover,
.arthistory-lesson-actions .btn-study-tool:hover,
.music-lesson-actions .btn-study-tool:hover,
.philosophy-lesson-actions .btn-study-tool:hover,
.linguistics-lesson-actions .btn-study-tool:hover,
.polisci-lesson-actions .btn-study-tool:hover,
.environment-lesson-actions .btn-study-tool:hover {
    background: var(--primary-color, #2563eb) !important;
    color: white !important;
    opacity: 1 !important;
    visibility: visible !important;
    transform: scale(1.05);
}

.civics-lesson-actions .btn-study-tool svg,
.economics-lesson-actions .btn-study-tool svg,
.geography-lesson-actions .btn-study-tool svg,
.sociology-lesson-actions .btn-study-tool svg,
.arthistory-lesson-actions .btn-study-tool svg,
.music-lesson-actions .btn-study-tool svg,
.philosophy-lesson-actions .btn-study-tool svg,
.linguistics-lesson-actions .btn-study-tool svg,
.polisci-lesson-actions .btn-study-tool svg,
.environment-lesson-actions .btn-study-tool svg {
    width: 24px;
    height: 24px;
    flex-shrink: 0;
}

.history-iframe-container {
    flex: 1;
    overflow: hidden;
}

.history-iframe-container iframe {
    width: 100%;
    height: 100%;
    border: none;
}

/* ============================================================
   Civics Screen - OpenStax Government Integration
   ============================================================ */
.civics-layout {
    display: flex;
    flex-direction: row;
    flex: 1;
    height: 100%;
    overflow: hidden;
}

.civics-left {
    width: 280px;
    min-width: 200px;
    max-width: 500px;
    background: var(--gray-50);
    border-right: 1px solid var(--gray-200);
    display: flex;
    flex-direction: column;
    transition: width 0.2s ease;
}

.civics-left.collapsed {
    width: 48px;
    min-width: 48px;
}

.civics-left.collapsed .civics-nav-content {
    display: none;
}

.civics-left.collapsed .civics-nav-header h3 {
    display: none;
}

.civics-nav-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 16px;
    background: linear-gradient(135deg, #1E3A5F, #2563EB);
    color: white;
}

.civics-nav-header h3 {
    margin: 0;
    font-size: 16px;
    font-weight: 600;
    white-space: nowrap;
}

.civics-collapse-btn {
    width: 24px;
    height: 24px;
    border: none;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 4px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    transition: background 0.15s;
    flex-shrink: 0;
}

.civics-collapse-btn:hover {
    background: rgba(255, 255, 255, 0.3);
}

.civics-left.collapsed .civics-collapse-btn .collapse-icon {
    transform: rotate(180deg);
}

.civics-nav-content {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
}

.civics-selector {
    margin-bottom: 16px;
}

.civics-selector label {
    display: block;
    font-size: 12px;
    font-weight: 600;
    color: var(--gray-500);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 6px;
}

.civics-selector select {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    background: white;
    cursor: pointer;
}

.civics-selector select:focus {
    outline: none;
    border-color: #2563EB;
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
}

.civics-lesson-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.civics-lesson-item {
    padding: 10px 12px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.15s;
    display: flex;
    align-items: center;
    gap: 10px;
}

.civics-lesson-item:hover {
    border-color: #2563EB;
    background: #EFF6FF;
}

.civics-lesson-item.active {
    background: #2563EB;
    border-color: #2563EB;
    color: white;
}

.civics-lesson-item .lesson-number {
    font-size: 11px;
    font-weight: 700;
    background: var(--gray-200);
    padding: 2px 6px;
    border-radius: 4px;
    flex-shrink: 0;
}

.civics-lesson-item.active .lesson-number {
    background: rgba(255, 255, 255, 0.2);
}

.civics-lesson-item .lesson-name {
    font-size: 13px;
    font-weight: 500;
}

.civics-resizer {
    width: 4px;
    background: var(--gray-200);
    cursor: col-resize;
    transition: background 0.15s;
}

.civics-resizer:hover,
.civics-resizer.resizing {
    background: #2563EB;
}

.civics-right {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: white;
}

.civics-lesson-placeholder {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.civics-lesson-placeholder .placeholder-content {
    text-align: center;
    color: var(--gray-500);
}

.civics-lesson-placeholder .placeholder-content p {
    margin: 12px 0 4px 0;
    font-size: 16px;
}

.civics-lesson-placeholder .placeholder-content .text-muted {
    font-size: 13px;
    margin: 4px 0 0 0;
}

.civics-lesson-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.civics-lesson-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 24px;
    border-bottom: 1px solid var(--gray-200);
    background: var(--gray-50);
}

.civics-lesson-header h2 {
    margin: 0;
    font-size: 18px;
    color: var(--gray-800);
}

.civics-lesson-actions {
    display: flex;
    gap: 8px;
}

.civics-lesson-actions .btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.civics-iframe-container {
    flex: 1;
    overflow: hidden;
}

.civics-iframe-container iframe {
    width: 100%;
    height: 100%;
    border: none;
}

/* ============================================================
   Economics Screen - OpenStax Integration
   ============================================================ */
.economics-layout {
    display: flex;
    flex-direction: row;
    flex: 1;
    height: 100%;
    overflow: hidden;
}

.economics-left {
    width: 280px;
    min-width: 200px;
    max-width: 500px;
    background: var(--gray-50);
    border-right: 1px solid var(--gray-200);
    display: flex;
    flex-direction: column;
    transition: width 0.2s ease;
}

.economics-left.collapsed {
    width: 48px;
    min-width: 48px;
}

.economics-left.collapsed .economics-nav-content {
    display: none;
}

.economics-left.collapsed .economics-nav-header h3 {
    display: none;
}

.economics-nav-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 16px;
    background: linear-gradient(135deg, #065F46, #059669);
    color: white;
}

.economics-nav-header h3 {
    margin: 0;
    font-size: 16px;
    font-weight: 600;
    white-space: nowrap;
}

.economics-collapse-btn {
    width: 24px;
    height: 24px;
    border: none;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 4px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    transition: background 0.15s;
    flex-shrink: 0;
}

.economics-collapse-btn:hover {
    background: rgba(255, 255, 255, 0.3);
}

.economics-left.collapsed .economics-collapse-btn .collapse-icon {
    transform: rotate(180deg);
}

.economics-nav-content {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
}

/* Economics Source Toggle (OpenStax / MIT) */
.economics-source-toggle {
    display: flex;
    gap: 16px;
    margin-bottom: 16px;
    padding: 12px;
    background: var(--gray-50);
    border-radius: var(--radius);
    border: 1px solid var(--gray-200);
}

.economics-source-toggle .economics-radio-label {
    display: flex !important;
    align-items: center;
    gap: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-700);
    margin-bottom: 0 !important;
}

.economics-source-toggle .economics-radio-label input[type="radio"] {
    width: 16px;
    height: 16px;
    cursor: pointer;
    accent-color: #059669;
    display: inline-block !important;
}

.economics-source-toggle .economics-radio-label:hover {
    color: #059669;
}

/* OpenStax Section */
.economics-openstax-section {
    display: block;
}

/* MIT Economics Section */
.economics-mit-section {
    display: block;
}

.economics-mit-course-selector {
    margin-bottom: 16px;
}

.economics-mit-course-selector select {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    background: white;
    cursor: pointer;
}

.economics-mit-course-selector select:focus {
    outline: none;
    border-color: #059669;
    box-shadow: 0 0 0 3px rgba(5, 150, 105, 0.15);
}

.economics-mit-chapter-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.economics-mit-chapter-item {
    display: flex;
    gap: 8px;
    border: 1px solid var(--gray-200);
    border-radius: var(--radius);
    background: white;
    padding: 10px 12px;
    cursor: pointer;
    transition: all 0.15s;
}

.economics-mit-chapter-item:hover {
    background: var(--gray-50);
    border-color: #059669;
}

.economics-mit-chapter-item.active {
    background: #059669;
    border-color: #059669;
    color: white;
}

.economics-mit-chapter-number {
    font-weight: 600;
    font-size: 13px;
    min-width: 24px;
}

.economics-mit-chapter-title {
    font-size: 13px;
    flex: 1;
}

.economics-mit-chapter-item.active .economics-mit-chapter-number,
.economics-mit-chapter-item.active .economics-mit-chapter-title {
    color: white;
}

.economics-selector {
    margin-bottom: 16px;
}

.economics-selector label {
    display: block;
    font-size: 12px;
    font-weight: 600;
    color: var(--gray-500);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 6px;
}

.economics-selector select {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    background: white;
    cursor: pointer;
}

.economics-selector select:focus {
    outline: none;
    border-color: #059669;
    box-shadow: 0 0 0 3px rgba(5, 150, 105, 0.15);
}

.economics-lesson-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.economics-lesson-item {
    padding: 10px 12px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.15s;
    display: flex;
    align-items: center;
    gap: 10px;
}

.economics-lesson-item:hover {
    border-color: #059669;
    background: #ECFDF5;
}

.economics-lesson-item.active {
    background: #059669;
    border-color: #059669;
    color: white;
}

.economics-lesson-item .lesson-number {
    font-size: 11px;
    font-weight: 700;
    background: var(--gray-200);
    padding: 2px 6px;
    border-radius: 4px;
    flex-shrink: 0;
}

.economics-lesson-item.active .lesson-number {
    background: rgba(255, 255, 255, 0.2);
}

.economics-lesson-item .lesson-name {
    font-size: 13px;
    font-weight: 500;
}

.economics-resizer {
    width: 4px;
    background: var(--gray-200);
    cursor: col-resize;
    transition: background 0.15s;
}

.economics-resizer:hover,
.economics-resizer.resizing {
    background: #059669;
}

.economics-right {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: white;
}

.economics-lesson-placeholder {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.economics-lesson-placeholder .placeholder-content {
    text-align: center;
    color: var(--gray-500);
}

.economics-lesson-placeholder .placeholder-content p {
    margin: 12px 0 4px 0;
    font-size: 16px;
}

.economics-lesson-placeholder .placeholder-content .text-muted {
    font-size: 13px;
    margin: 4px 0 0 0;
}

.economics-lesson-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.economics-lesson-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 24px;
    border-bottom: 1px solid var(--gray-200);
    background: var(--gray-50);
}

.economics-lesson-header h2 {
    margin: 0;
    font-size: 18px;
    color: var(--gray-800);
}

.economics-lesson-actions {
    display: flex;
    gap: 8px;
}

.economics-lesson-actions .btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.economics-iframe-container {
    flex: 1;
    overflow: hidden;
}

.economics-iframe-container iframe {
    width: 100%;
    height: 100%;
    border: none;
}

/* =========================================================================
   GEOGRAPHY SCREEN STYLES - Teal Theme (#0D9488)
   ========================================================================= */
.geography-layout {
    display: flex;
    flex-direction: row;
    flex: 1;
    height: 100%;
    overflow: hidden;
}

.geography-left {
    width: 280px;
    min-width: 200px;
    max-width: 500px;
    background: var(--gray-50);
    border-right: 1px solid var(--gray-200);
    display: flex;
    flex-direction: column;
    transition: width 0.2s ease;
}

.geography-left.collapsed {
    width: 48px;
    min-width: 48px;
}

.geography-left.collapsed .geography-nav-content {
    display: none;
}

.geography-left.collapsed .geography-nav-header h3 {
    display: none;
}

.geography-nav-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 16px;
    background: linear-gradient(135deg, #0F766E, #0D9488);
    color: white;
}

.geography-nav-header h3 {
    margin: 0;
    font-size: 16px;
    font-weight: 600;
    white-space: nowrap;
}

.geography-collapse-btn {
    width: 24px;
    height: 24px;
    border: none;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 4px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    transition: background 0.15s;
    flex-shrink: 0;
}

.geography-collapse-btn:hover {
    background: rgba(255, 255, 255, 0.3);
}

.geography-left.collapsed .geography-collapse-btn .collapse-icon {
    transform: rotate(180deg);
}

.geography-nav-content {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
}

.geography-selector {
    margin-bottom: 16px;
}

.geography-selector label {
    display: block;
    font-size: 12px;
    font-weight: 600;
    color: var(--gray-500);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 6px;
}

.geography-selector select {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    background: white;
    cursor: pointer;
}

.geography-selector select:focus {
    outline: none;
    border-color: #0D9488;
    box-shadow: 0 0 0 3px rgba(13, 148, 136, 0.15);
}

.geography-lesson-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.geography-lesson-item {
    padding: 10px 12px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.15s;
    display: flex;
    align-items: center;
    gap: 10px;
}

.geography-lesson-item:hover {
    border-color: #0D9488;
    background: #F0FDFA;
}

.geography-lesson-item.active {
    background: #0D9488;
    border-color: #0D9488;
    color: white;
}

.geography-lesson-item .lesson-number {
    font-size: 11px;
    font-weight: 700;
    background: var(--gray-200);
    padding: 2px 6px;
    border-radius: 4px;
    flex-shrink: 0;
}

.geography-lesson-item.active .lesson-number {
    background: rgba(255, 255, 255, 0.2);
}

.geography-lesson-item .lesson-name {
    font-size: 13px;
    font-weight: 500;
}

.geography-resizer {
    width: 4px;
    background: var(--gray-200);
    cursor: col-resize;
    transition: background 0.15s;
}

.geography-resizer:hover,
.geography-resizer.resizing {
    background: #0D9488;
}

.geography-right {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: white;
}

.geography-lesson-placeholder {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.geography-lesson-placeholder .placeholder-content {
    text-align: center;
    color: var(--gray-500);
}

.geography-lesson-placeholder .placeholder-content p {
    margin: 12px 0 4px 0;
    font-size: 16px;
}

.geography-lesson-placeholder .placeholder-content .text-muted {
    font-size: 13px;
    margin: 4px 0 0 0;
}

.geography-lesson-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.geography-lesson-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 24px;
    border-bottom: 1px solid var(--gray-200);
    background: var(--gray-50);
}

.geography-lesson-header h2 {
    margin: 0;
    font-size: 18px;
    color: var(--gray-800);
}

.geography-lesson-actions {
    display: flex;
    gap: 8px;
}

.geography-lesson-actions .btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.geography-iframe-container {
    flex: 1;
    overflow: hidden;
}

.geography-iframe-container iframe {
    width: 100%;
    height: 100%;
    border: none;
}

/* =========================================================================
   SOCIOLOGY/PSYCHOLOGY SCREEN STYLES - Purple Theme (#7C3AED)
   ========================================================================= */
.sociology-layout {
    display: flex;
    flex-direction: row;
    flex: 1;
    height: 100%;
    overflow: hidden;
}

.sociology-left {
    width: 280px;
    min-width: 200px;
    max-width: 500px;
    background: var(--gray-50);
    border-right: 1px solid var(--gray-200);
    display: flex;
    flex-direction: column;
    transition: width 0.2s ease;
}

.sociology-left.collapsed {
    width: 48px;
    min-width: 48px;
}

.sociology-left.collapsed .sociology-nav-content {
    display: none;
}

.sociology-left.collapsed .sociology-nav-header h3 {
    display: none;
}

.sociology-nav-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 16px;
    background: linear-gradient(135deg, #5B21B6, #7C3AED);
    color: white;
}

.sociology-nav-header h3 {
    margin: 0;
    font-size: 16px;
    font-weight: 600;
    white-space: nowrap;
}

.sociology-collapse-btn {
    width: 24px;
    height: 24px;
    border: none;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 4px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    transition: background 0.15s;
    flex-shrink: 0;
}

.sociology-collapse-btn:hover {
    background: rgba(255, 255, 255, 0.3);
}

.sociology-left.collapsed .sociology-collapse-btn .collapse-icon {
    transform: rotate(180deg);
}

.sociology-nav-content {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
}

.sociology-selector {
    margin-bottom: 16px;
}

.sociology-selector label {
    display: block;
    font-size: 12px;
    font-weight: 600;
    color: var(--gray-500);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 6px;
}

.sociology-selector select {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    background: white;
    cursor: pointer;
}

.sociology-selector select:focus {
    outline: none;
    border-color: #7C3AED;
    box-shadow: 0 0 0 3px rgba(124, 58, 237, 0.15);
}

.sociology-lesson-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.sociology-lesson-item {
    padding: 10px 12px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.15s;
    display: flex;
    align-items: center;
    gap: 10px;
}

.sociology-lesson-item:hover {
    border-color: #7C3AED;
    background: #F5F3FF;
}

.sociology-lesson-item.active {
    background: #7C3AED;
    border-color: #7C3AED;
    color: white;
}

.sociology-lesson-item .lesson-number {
    font-size: 11px;
    font-weight: 700;
    background: var(--gray-200);
    padding: 2px 6px;
    border-radius: 4px;
    flex-shrink: 0;
}

.sociology-lesson-item.active .lesson-number {
    background: rgba(255, 255, 255, 0.2);
}

.sociology-lesson-item .lesson-name {
    font-size: 13px;
    font-weight: 500;
}

.sociology-resizer {
    width: 4px;
    background: var(--gray-200);
    cursor: col-resize;
    transition: background 0.15s;
}

.sociology-resizer:hover,
.sociology-resizer.resizing {
    background: #7C3AED;
}

.sociology-right {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: white;
}

.sociology-lesson-placeholder {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.sociology-lesson-placeholder .placeholder-content {
    text-align: center;
    color: var(--gray-500);
}

.sociology-lesson-placeholder .placeholder-content p {
    margin: 12px 0 4px 0;
    font-size: 16px;
}

.sociology-lesson-placeholder .placeholder-content .text-muted {
    font-size: 13px;
    margin: 4px 0 0 0;
}

.sociology-lesson-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.sociology-lesson-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 24px;
    border-bottom: 1px solid var(--gray-200);
    background: var(--gray-50);
}

.sociology-lesson-header h2 {
    margin: 0;
    font-size: 18px;
    color: var(--gray-800);
}

.sociology-lesson-actions {
    display: flex;
    gap: 8px;
}

.sociology-lesson-actions .btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.sociology-iframe-container {
    flex: 1;
    overflow: hidden;
}

.sociology-iframe-container iframe {
    width: 100%;
    height: 100%;
    border: none;
}

/* =========================================================================
   ART HISTORY SCREEN STYLES - Rose/Burgundy Theme (#BE185D)
   ========================================================================= */
.arthistory-layout {
    display: flex;
    flex-direction: row;
    flex: 1;
    height: 100%;
    overflow: hidden;
}

.arthistory-left {
    width: 280px;
    min-width: 200px;
    max-width: 500px;
    background: var(--gray-50);
    border-right: 1px solid var(--gray-200);
    display: flex;
    flex-direction: column;
    transition: width 0.2s ease;
    overflow: hidden;
}

.arthistory-left.collapsed {
    width: 48px;
    min-width: 48px;
}

.arthistory-left.collapsed .arthistory-nav-content {
    display: none;
}

.arthistory-left.collapsed .arthistory-nav-header h3 {
    display: none;
}

.arthistory-nav-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 16px;
    background: linear-gradient(135deg, #9D174D, #BE185D);
    color: white;
}

.arthistory-nav-header h3 {
    margin: 0;
    font-size: 16px;
    font-weight: 600;
    white-space: nowrap;
}

.arthistory-collapse-btn {
    width: 24px;
    height: 24px;
    border: none;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 4px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    transition: background 0.15s;
    flex-shrink: 0;
}

.arthistory-collapse-btn:hover {
    background: rgba(255, 255, 255, 0.3);
}

.arthistory-left.collapsed .arthistory-collapse-btn .collapse-icon {
    transform: rotate(180deg);
}

.arthistory-nav-content {
    flex: 1;
    overflow-x: hidden;
    overflow-y: auto;
    padding: 16px;
}

.arthistory-selector {
    margin-bottom: 16px;
    overflow: hidden;
}

.arthistory-selector label {
    display: block;
    font-size: 12px;
    font-weight: 600;
    color: var(--gray-500);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 6px;
}

.arthistory-selector select {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    background: white;
    cursor: pointer;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.arthistory-selector select:focus {
    outline: none;
    border-color: #BE185D;
    box-shadow: 0 0 0 3px rgba(190, 24, 93, 0.15);
}

.arthistory-lesson-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.arthistory-lesson-item {
    padding: 10px 12px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.15s;
    display: flex;
    align-items: center;
    gap: 10px;
    min-width: 0;
}

.arthistory-lesson-item:hover {
    border-color: #BE185D;
    background: #FDF2F8;
}

.arthistory-lesson-item.active {
    background: #BE185D;
    border-color: #BE185D;
    color: white;
}

.arthistory-lesson-item .lesson-number {
    font-size: 11px;
    font-weight: 700;
    background: var(--gray-200);
    padding: 2px 6px;
    border-radius: 4px;
    flex-shrink: 0;
}

.arthistory-lesson-item.active .lesson-number {
    background: rgba(255, 255, 255, 0.2);
}

.arthistory-lesson-item .lesson-name {
    font-size: 13px;
    font-weight: 500;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    min-width: 0;
}

.arthistory-resizer {
    width: 4px;
    background: var(--gray-200);
    cursor: col-resize;
    transition: background 0.15s;
}

.arthistory-resizer:hover,
.arthistory-resizer.resizing {
    background: #BE185D;
}

.arthistory-right {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: white;
}

.arthistory-lesson-placeholder {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.arthistory-lesson-placeholder .placeholder-content {
    text-align: center;
    color: var(--gray-500);
}

.arthistory-lesson-placeholder .placeholder-content p {
    margin: 12px 0 4px 0;
    font-size: 16px;
}

.arthistory-lesson-placeholder .placeholder-content .text-muted {
    font-size: 13px;
    margin: 4px 0 0 0;
}

.arthistory-lesson-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.arthistory-lesson-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 24px;
    border-bottom: 1px solid var(--gray-200);
    background: var(--gray-50);
}

.arthistory-lesson-header h2 {
    margin: 0;
    font-size: 18px;
    color: var(--gray-800);
}

.arthistory-lesson-actions {
    display: flex;
    gap: 8px;
}

.arthistory-lesson-actions .btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.arthistory-iframe-container {
    flex: 1;
    overflow: hidden;
}

.arthistory-iframe-container iframe {
    width: 100%;
    height: 100%;
    border: none;
}

/* =========================================================================
   MUSIC SCREEN STYLES - Purple Theme (#7C3AED)
   ========================================================================= */
.music-layout {
    display: flex;
    flex-direction: row;
    flex: 1;
    height: 100%;
    overflow: hidden;
}

.music-left {
    width: 280px;
    min-width: 200px;
    max-width: 500px;
    background: var(--gray-50);
    border-right: 1px solid var(--gray-200);
    display: flex;
    flex-direction: column;
    transition: width 0.2s;
}

.music-left.collapsed {
    width: 48px;
    min-width: 48px;
}

.music-left.collapsed .music-nav-content {
    display: none;
}

.music-left.collapsed .music-nav-header h3 {
    display: none;
}

.music-nav-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 16px;
    background: linear-gradient(135deg, #6D28D9, #7C3AED);
    color: white;
}

.music-nav-header h3 {
    margin: 0;
    font-size: 16px;
    font-weight: 600;
    white-space: nowrap;
}

.music-collapse-btn {
    width: 24px;
    height: 24px;
    border: none;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 4px;
    color: white;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.15s;
}

.music-collapse-btn:hover {
    background: rgba(255, 255, 255, 0.3);
}

.music-left.collapsed .music-collapse-btn .collapse-icon {
    transform: rotate(180deg);
}

.music-nav-content {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
}

/* Music Source Toggle (Teoria / MIT) */
.music-source-toggle {
    display: flex;
    gap: 16px;
    margin-bottom: 16px;
    padding: 12px;
    background: var(--gray-50);
    border-radius: var(--radius);
    border: 1px solid var(--gray-200);
}

.music-source-toggle .music-radio-label {
    display: flex !important;
    align-items: center;
    gap: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    color: var(--gray-700);
    margin-bottom: 0 !important;
}

.music-source-toggle .music-radio-label input[type="radio"] {
    width: 16px;
    height: 16px;
    cursor: pointer;
    accent-color: #7C3AED;
    display: inline-block !important;
}

.music-source-toggle .music-radio-label:hover {
    color: #7C3AED;
}

/* Music course select dropdown */
.music-course-select {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--border-color, #e5e7eb);
    border-radius: 8px;
    font-size: 0.9rem;
    background: var(--bg-primary, #fff);
    cursor: pointer;
    margin-bottom: 16px;
}

.music-course-select:focus {
    outline: none;
    border-color: #7C3AED;
    box-shadow: 0 0 0 3px rgba(124, 58, 237, 0.15);
}

.music-selector {
    margin-bottom: 16px;
}

.music-selector label {
    display: block;
    font-size: 12px;
    font-weight: 600;
    color: var(--gray-500);
    text-transform: uppercase;
    margin-bottom: 6px;
}

.music-selector select {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    background: white;
}

.music-selector select:focus {
    outline: none;
    border-color: #7C3AED;
    box-shadow: 0 0 0 3px rgba(124, 58, 237, 0.15);
}

.music-lesson-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.music-lesson-item {
    padding: 10px 12px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: 6px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 10px;
    transition: all 0.15s;
}

.music-lesson-item:hover {
    border-color: #7C3AED;
    background: #F5F3FF;
}

.music-lesson-item.active {
    background: #7C3AED;
    border-color: #7C3AED;
    color: white;
}

.music-lesson-item .lesson-number {
    font-size: 11px;
    font-weight: 700;
    background: var(--gray-200);
    padding: 2px 6px;
    border-radius: 4px;
}

.music-lesson-item.active .lesson-number {
    background: rgba(255, 255, 255, 0.2);
}

.music-lesson-item .lesson-name {
    font-size: 13px;
    font-weight: 500;
}

.music-resizer {
    width: 4px;
    background: var(--gray-200);
    cursor: col-resize;
    transition: background 0.15s;
}

.music-resizer:hover,
.music-resizer.resizing {
    background: #7C3AED;
}

.music-right {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: white;
}

.music-lesson-placeholder {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.music-lesson-placeholder .placeholder-content {
    text-align: center;
    color: var(--gray-500);
}

.music-lesson-placeholder .placeholder-content p {
    margin: 12px 0 4px 0;
    font-size: 16px;
}

.music-lesson-placeholder .placeholder-content .text-muted {
    font-size: 13px;
    margin: 4px 0 0 0;
}

.music-lesson-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.music-lesson-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 24px;
    border-bottom: 1px solid var(--gray-200);
    background: var(--gray-50);
}

.music-lesson-header h2 {
    margin: 0;
    font-size: 18px;
    color: var(--gray-800);
}

.music-lesson-actions {
    display: flex;
    gap: 8px;
}

.music-lesson-actions .btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.music-iframe-container {
    flex: 1;
    overflow: hidden;
}

.music-iframe-container iframe {
    width: 100%;
    height: 100%;
    border: none;
}

/* =========================================================================
   PHILOSOPHY SCREEN STYLES - Teal Theme (#0D9488)
   ========================================================================= */
.philosophy-layout {
    display: flex;
    flex-direction: row;
    flex: 1;
    height: 100%;
    overflow: hidden;
}

.philosophy-left {
    width: 280px;
    min-width: 200px;
    max-width: 500px;
    background: var(--gray-50);
    border-right: 1px solid var(--gray-200);
    display: flex;
    flex-direction: column;
    transition: width 0.2s;
}

.philosophy-left.collapsed {
    width: 48px;
    min-width: 48px;
}

.philosophy-left.collapsed .philosophy-nav-content {
    display: none;
}

.philosophy-left.collapsed .philosophy-nav-header h3 {
    display: none;
}

.philosophy-nav-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 16px;
    background: linear-gradient(135deg, #0F766E, #0D9488);
    color: white;
}

.philosophy-nav-header h3 {
    margin: 0;
    font-size: 16px;
    font-weight: 600;
    white-space: nowrap;
}

.philosophy-collapse-btn {
    width: 24px;
    height: 24px;
    border: none;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 4px;
    color: white;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.15s;
}

.philosophy-collapse-btn:hover {
    background: rgba(255, 255, 255, 0.3);
}

.philosophy-left.collapsed .philosophy-collapse-btn .collapse-icon {
    transform: rotate(180deg);
}

.philosophy-nav-content {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
}

.philosophy-selector {
    margin-bottom: 16px;
}

.philosophy-selector label {
    display: block;
    font-size: 12px;
    font-weight: 600;
    color: var(--gray-500);
    text-transform: uppercase;
    margin-bottom: 6px;
}

.philosophy-selector select {
    width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    background: white;
}

.philosophy-selector select:focus {
    outline: none;
    border-color: #0D9488;
    box-shadow: 0 0 0 3px rgba(13, 148, 136, 0.15);
}

.philosophy-lesson-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.philosophy-lesson-item {
    padding: 10px 12px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: 6px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 10px;
    transition: all 0.15s;
}

.philosophy-lesson-item:hover {
    border-color: #0D9488;
    background: #F0FDFA;
}

.philosophy-lesson-item.active {
    background: #0D9488;
    border-color: #0D9488;
    color: white;
}

.philosophy-lesson-item .lesson-number {
    font-size: 11px;
    font-weight: 700;
    background: var(--gray-200);
    padding: 2px 6px;
    border-radius: 4px;
}

.philosophy-lesson-item.active .lesson-number {
    background: rgba(255, 255, 255, 0.2);
}

.philosophy-lesson-item .lesson-name {
    font-size: 13px;
    font-weight: 500;
}

.philosophy-resizer {
    width: 4px;
    background: var(--gray-200);
    cursor: col-resize;
    transition: background 0.15s;
}

.philosophy-resizer:hover,
.philosophy-resizer.resizing {
    background: #0D9488;
}

.philosophy-right {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: white;
}

.philosophy-lesson-placeholder {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.philosophy-lesson-placeholder .placeholder-content {
    text-align: center;
    color: var(--gray-500);
}

.philosophy-lesson-placeholder .placeholder-content p {
    margin: 12px 0 4px 0;
    font-size: 16px;
}

.philosophy-lesson-placeholder .placeholder-content .text-muted {
    font-size: 13px;
    margin: 4px 0 0 0;
}

.philosophy-lesson-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.philosophy-lesson-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 24px;
    border-bottom: 1px solid var(--gray-200);
    background: var(--gray-50);
}

.philosophy-lesson-header h2 {
    margin: 0;
    font-size: 18px;
    color: var(--gray-800);
}

.philosophy-lesson-actions {
    display: flex;
    gap: 8px;
}

.philosophy-lesson-actions .btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.philosophy-iframe-container {
    flex: 1;
    overflow: hidden;
}

.philosophy-iframe-container iframe {
    width: 100%;
    height: 100%;
    border: none;
}

/* =========================================================================
   LINGUISTICS SCREEN STYLES - Purple Theme (#7C3AED)
   ========================================================================= */
.linguistics-layout {
    display: flex;
    flex-direction: row;
    flex: 1;
    height: 100%;
    overflow: hidden;
}

.linguistics-left {
    width: 280px;
    min-width: 200px;
    max-width: 500px;
    background: var(--gray-50);
    border-right: 1px solid var(--gray-200);
    display: flex;
    flex-direction: column;
    flex-shrink: 0;
    overflow: hidden;
    transition: width 0.2s;
}

.linguistics-left.collapsed {
    width: 48px;
    min-width: 48px;
}

.linguistics-left.collapsed .linguistics-nav-content {
    display: none;
}

.linguistics-left.collapsed .linguistics-nav-header h3 {
    display: none;
}

.linguistics-nav-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 16px;
    background: linear-gradient(135deg, #6D28D9, #7C3AED);
    color: white;
}

.linguistics-nav-header h3 {
    margin: 0;
    font-size: 16px;
    font-weight: 600;
    white-space: nowrap;
}

.linguistics-collapse-btn {
    width: 24px;
    height: 24px;
    border: none;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 4px;
    color: white;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.15s;
}

.linguistics-collapse-btn:hover {
    background: rgba(255, 255, 255, 0.3);
}

.linguistics-left.collapsed .linguistics-collapse-btn .collapse-icon {
    transform: rotate(180deg);
}

.linguistics-nav-content {
    flex: 1;
    overflow-y: auto;
    overflow-x: hidden;
    padding: 16px;
    max-width: 100%;
    box-sizing: border-box;
}

.linguistics-selector {
    margin-bottom: 16px;
    overflow: hidden;
    max-width: 100%;
}

.linguistics-selector label {
    display: block;
    font-size: 12px;
    font-weight: 600;
    color: var(--gray-500);
    text-transform: uppercase;
    margin-bottom: 6px;
}

.linguistics-selector select {
    width: 100%;
    max-width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    background: white;
    box-sizing: border-box;
    overflow: hidden;
    text-overflow: ellipsis;
}

.linguistics-selector select:focus {
    outline: none;
    border-color: #7C3AED;
    box-shadow: 0 0 0 3px rgba(124, 58, 237, 0.15);
}

.linguistics-lesson-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.linguistics-lesson-item {
    padding: 10px 12px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: 6px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 10px;
    transition: all 0.15s;
}

.linguistics-lesson-item:hover {
    border-color: #7C3AED;
    background: #F5F3FF;
}

.linguistics-lesson-item.active {
    background: #7C3AED;
    border-color: #7C3AED;
    color: white;
}

.linguistics-lesson-item .lesson-number {
    font-size: 11px;
    font-weight: 700;
    background: var(--gray-200);
    padding: 2px 6px;
    border-radius: 4px;
}

.linguistics-lesson-item.active .lesson-number {
    background: rgba(255, 255, 255, 0.2);
}

.linguistics-lesson-item .lesson-name {
    font-size: 13px;
    font-weight: 500;
}

.linguistics-resizer {
    width: 4px;
    background: var(--gray-200);
    cursor: col-resize;
    transition: background 0.15s;
}

.linguistics-resizer:hover,
.linguistics-resizer.resizing {
    background: #7C3AED;
}

.linguistics-right {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: white;
}

.linguistics-lesson-placeholder {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.linguistics-lesson-placeholder .placeholder-content {
    text-align: center;
    color: var(--gray-500);
}

.linguistics-lesson-placeholder .placeholder-content p {
    margin: 12px 0 4px 0;
    font-size: 16px;
}

.linguistics-lesson-placeholder .placeholder-content .text-muted {
    font-size: 13px;
    margin: 4px 0 0 0;
}

.linguistics-lesson-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.linguistics-lesson-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 16px 24px;
    border-bottom: 1px solid var(--gray-200);
    background: var(--gray-50);
}

.linguistics-lesson-header h2 {
    margin: 0;
    font-size: 18px;
    color: var(--gray-800);
}

.linguistics-lesson-actions {
    display: flex;
    flex-direction: row;
    gap: 8px;
}

.linguistics-iframe-container {
    flex: 1;
    overflow: hidden;
}

.linguistics-iframe-container iframe {
    width: 100%;
    height: 100%;
    border: none;
}

/* =========================================================================
   POLITICAL SCIENCE SCREEN STYLES - Navy Blue Theme (#1E3A5F)
   ========================================================================= */
.polisci-layout {
    display: flex;
    flex-direction: row;
    flex: 1;
    height: 100%;
    overflow: hidden;
}

.polisci-left {
    width: 280px;
    min-width: 200px;
    max-width: 500px;
    background: var(--gray-50);
    border-right: 1px solid var(--gray-200);
    display: flex;
    flex-direction: column;
    flex-shrink: 0;
    overflow: hidden;
    transition: width 0.2s;
}

.polisci-left.collapsed {
    width: 48px;
    min-width: 48px;
}

.polisci-left.collapsed .polisci-nav-content {
    display: none;
}

.polisci-left.collapsed .polisci-nav-header h3 {
    display: none;
}

.polisci-nav-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 16px;
    background: linear-gradient(135deg, #1E3A5F, #2C5282);
    color: white;
}

.polisci-nav-header h3 {
    margin: 0;
    font-size: 16px;
    font-weight: 600;
    white-space: nowrap;
}

.polisci-collapse-btn {
    width: 24px;
    height: 24px;
    border: none;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 4px;
    color: white;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background 0.15s;
}

.polisci-collapse-btn:hover {
    background: rgba(255, 255, 255, 0.3);
}

.polisci-left.collapsed .polisci-collapse-btn .collapse-icon {
    transform: rotate(180deg);
}

.polisci-nav-content {
    flex: 1;
    overflow-y: auto;
    overflow-x: hidden;
    padding: 16px;
    max-width: 100%;
    box-sizing: border-box;
}

.polisci-selector {
    margin-bottom: 16px;
    overflow: hidden;
    max-width: 100%;
}

.polisci-selector label {
    display: block;
    font-size: 12px;
    font-weight: 600;
    color: var(--gray-500);
    text-transform: uppercase;
    margin-bottom: 6px;
}

.polisci-selector select {
    width: 100%;
    max-width: 100%;
    padding: 8px 12px;
    border: 1px solid var(--gray-300);
    border-radius: 6px;
    font-size: 14px;
    background: white;
    box-sizing: border-box;
    overflow: hidden;
    text-overflow: ellipsis;
}

.polisci-selector select:focus {
    outline: none;
    border-color: #1E3A5F;
    box-shadow: 0 0 0 3px rgba(30, 58, 95, 0.15);
}

.polisci-lesson-list {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.polisci-lesson-item {
    padding: 10px 12px;
    background: white;
    border: 1px solid var(--gray-200);
    border-radius: 6px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 10px;
    transition: all 0.15s;
}

.polisci-lesson-item:hover {
    border-color: #1E3A5F;
    background: #EBF4FF;
}

.polisci-lesson-item.active {
    background: #1E3A5F;
    border-color: #1E3A5F;
    color: white;
}

.polisci-lesson-item .lesson-number {
    font-size: 11px;
    font-weight: 700;
    background: var(--gray-200);
    padding: 2px 6px;
    border-radius: 4px;
}

.polisci-lesson-item.active .lesson-number {
    background: rgba(255, 255, 255, 0.2);
}

.polisci-lesson-item .lesson-name {
    font-size: 13px;
    font-weight: 500;
}

.polisci-resizer {
    width: 4px;
    background: var(--gray-200);
    cursor: col-resize;
    transition: background 0.15s;
}

.polisci-resizer:hover,
.polisci-resizer.resizing {
    background: #1E3A5F;
}

.polisci-right {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: white;
}

.polisci-lesson-placeholder {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
}

.polisci-lesson-placeholder .placeholder-content {
    text-align: center;
    color: var(--gray-500);
}

.polisci-lesson-placeholder .placeholder-content p {
    margin: 12px 0 4px 0;
    font-size: 16px;
}

.polisci-lesson-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.polisci-lesson-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 16px;
    border-bottom: 1px solid var(--gray-200);
    background: var(--gray-50);
}

.polisci-lesson-header h2 {
    margin: 0;
    font-size: 18px;
    color: var(--gray-800);
}

.polisci-lesson-actions {
    display: flex;
    flex-direction: row;
    gap: 8px;
}

.polisci-iframe-container {
    flex: 1;
    overflow: hidden;
}

.polisci-iframe-container iframe {
    width: 100%;
    height: 100%;
    border: none;
}

/* ============================================================
   Environmental Science Screen - LibreTexts Integration
   ============================================================ */
.environment-layout {
    display: flex;
    flex-direction: row;
    flex: 1;
    height: 100%;
    overflow: hidden;
}

.environment-left {
    width: 280px;
    min-width: 200px;
    max-width: 400px;
    display: flex;
    flex-direction: column;
    background: var(--bg-primary, #fff);
    border-right: 1px solid var(--border-color, #e5e7eb);
    transition: width 0.2s;
}

.environment-left.collapsed {
    width: 48px;
    min-width: 48px;
}

.environment-left.collapsed .environment-nav-content {
    display: none;
}

.environment-left.collapsed .environment-nav-header h3 {
    display: none;
}

.environment-nav-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 16px;
    border-bottom: 1px solid var(--border-color, #e5e7eb);
    background: var(--bg-secondary, #f9fafb);
}

.environment-nav-header h3 {
    margin: 0;
    font-size: 1rem;
    font-weight: 600;
    white-space: nowrap;
}

.environment-collapse-btn {
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
    color: var(--text-secondary, #6b7280);
    transition: color 0.2s;
}

.environment-collapse-btn:hover {
    color: var(--primary-color, #2563eb);
}

.environment-nav-content {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
}

.environment-selector {
    margin-bottom: 16px;
}

.environment-selector label {
    display: block;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-secondary, #6b7280);
    margin-bottom: 6px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.environment-selector select {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--border-color, #e5e7eb);
    border-radius: 8px;
    font-size: 0.9rem;
    background: var(--bg-primary, #fff);
    cursor: pointer;
}

.environment-lesson-list {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.environment-lesson-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px;
    border-radius: 8px;
    cursor: pointer;
    transition: background 0.2s;
}

.environment-lesson-item:hover {
    background: var(--bg-secondary, #f3f4f6);
}

.environment-lesson-item.active {
    background: var(--primary-light, #dbeafe);
    color: var(--primary-color, #2563eb);
}

.environment-lesson-item .lesson-number {
    font-weight: 600;
    font-size: 0.85rem;
    color: var(--text-secondary, #6b7280);
    min-width: 24px;
}

.environment-lesson-item.active .lesson-number {
    color: var(--primary-color, #2563eb);
}

.environment-lesson-item .lesson-title {
    font-size: 0.9rem;
    flex: 1;
}

.environment-resizer {
    width: 4px;
    background: var(--border-color, #e5e7eb);
    cursor: col-resize;
    transition: background 0.2s;
}

.environment-resizer:hover,
.environment-resizer.resizing {
    background: var(--primary-color, #2563eb);
}

.environment-right {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.environment-lesson-placeholder {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: var(--text-secondary, #6b7280);
}

.environment-lesson-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.environment-lesson-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 20px;
    border-bottom: 1px solid var(--border-color, #e5e7eb);
    background: var(--bg-primary, #fff);
}

.environment-lesson-header h2 {
    margin: 0;
    font-size: 1.1rem;
    font-weight: 600;
}

.environment-lesson-actions {
    display: flex;
    align-items: center;
    gap: 8px;
}

.environment-lesson-actions .btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.environment-iframe-container {
    flex: 1;
    overflow: hidden;
}

.environment-iframe-container iframe {
    width: 100%;
    height: 100%;
    border: none;
}

/* =========================================================================
   COMPUTER SCIENCE SCREEN
   ========================================================================= */

.cs-layout {
    display: flex;
    flex-direction: row;
    flex: 1;
    height: 100%;
    overflow: hidden;
}

.cs-left {
    width: 280px;
    min-width: 200px;
    max-width: 400px;
    display: flex;
    flex-direction: column;
    background: var(--bg-primary, #fff);
    border-right: 1px solid var(--border-color, #e5e7eb);
    transition: width 0.2s;
}

.cs-left.collapsed {
    width: 48px;
    min-width: 48px;
}

.cs-left.collapsed .cs-nav-content {
    display: none;
}

.cs-left.collapsed .cs-nav-header h3 {
    display: none;
}

.cs-nav-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 16px;
    border-bottom: 1px solid var(--border-color, #e5e7eb);
    background: var(--bg-secondary, #f9fafb);
}

.cs-nav-header h3 {
    margin: 0;
    font-size: 1rem;
    font-weight: 600;
    white-space: nowrap;
}

.cs-collapse-btn {
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
    color: var(--text-secondary, #6b7280);
    transition: color 0.2s;
}

.cs-collapse-btn:hover {
    color: var(--primary-color, #2563eb);
}

.cs-nav-content {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
}

.cs-selector {
    margin-bottom: 16px;
}

.cs-selector label {
    display: block;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-secondary, #6b7280);
    margin-bottom: 6px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.cs-selector select {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--border-color, #e5e7eb);
    border-radius: 8px;
    font-size: 0.9rem;
    background: var(--bg-primary, #fff);
    cursor: pointer;
}

.cs-lesson-list {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.cs-lesson-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px;
    border-radius: 8px;
    cursor: pointer;
    transition: background 0.2s;
}

.cs-lesson-item:hover {
    background: var(--bg-secondary, #f3f4f6);
}

.cs-lesson-item.active {
    background: var(--primary-light, #dbeafe);
    color: var(--primary-color, #2563eb);
}

.cs-lesson-item .lesson-number {
    font-weight: 600;
    font-size: 0.85rem;
    color: var(--text-secondary, #6b7280);
    min-width: 24px;
}

.cs-lesson-item.active .lesson-number {
    color: var(--primary-color, #2563eb);
}

.cs-lesson-item .lesson-title {
    font-size: 0.9rem;
    flex: 1;
}

.cs-resizer {
    width: 4px;
    background: var(--border-color, #e5e7eb);
    cursor: col-resize;
    transition: background 0.2s;
}

.cs-resizer:hover,
.cs-resizer.resizing {
    background: var(--primary-color, #2563eb);
}

.cs-right {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.cs-lesson-placeholder {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: var(--text-secondary, #6b7280);
}

.cs-lesson-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.cs-lesson-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 20px;
    border-bottom: 1px solid var(--border-color, #e5e7eb);
    background: var(--bg-primary, #fff);
}

.cs-lesson-header h2 {
    margin: 0;
    font-size: 1.1rem;
    font-weight: 600;
}

.cs-lesson-actions {
    display: flex;
    align-items: center;
    gap: 8px;
}

.cs-lesson-actions .btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.cs-iframe-container {
    flex: 1;
    overflow: hidden;
}

.cs-iframe-container iframe {
    width: 100%;
    height: 100%;
    border: none;
}

/* =========================================================================
   PERSONAL FINANCE SCREEN STYLES
   ========================================================================= */

.finance-layout {
    display: flex;
    flex-direction: row;
    flex: 1;
    height: 100%;
    overflow: hidden;
}

.finance-left {
    width: 280px;
    min-width: 200px;
    max-width: 400px;
    display: flex;
    flex-direction: column;
    background: var(--bg-primary, #fff);
    border-right: 1px solid var(--border-color, #e5e7eb);
    transition: width 0.2s;
}

.finance-left.collapsed {
    width: 48px;
    min-width: 48px;
}

.finance-left.collapsed .finance-nav-content {
    display: none;
}

.finance-left.collapsed .finance-nav-header h3 {
    display: none;
}

.finance-nav-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 12px 16px;
    border-bottom: 1px solid var(--border-color, #e5e7eb);
    background: var(--bg-secondary, #f9fafb);
}

.finance-nav-header h3 {
    margin: 0;
    font-size: 1rem;
    font-weight: 600;
    white-space: nowrap;
}

.finance-collapse-btn {
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
    color: var(--text-secondary, #6b7280);
    transition: color 0.2s;
}

.finance-collapse-btn:hover {
    color: var(--primary-color, #2563eb);
}

.finance-nav-content {
    flex: 1;
    overflow-y: auto;
    padding: 16px;
}

.finance-selector {
    margin-bottom: 16px;
}

.finance-selector label {
    display: block;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-secondary, #6b7280);
    margin-bottom: 6px;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.finance-selector select {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid var(--border-color, #e5e7eb);
    border-radius: 8px;
    font-size: 0.9rem;
    background: var(--bg-primary, #fff);
    cursor: pointer;
}

.finance-lesson-list {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.finance-lesson-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px;
    border-radius: 8px;
    cursor: pointer;
    transition: background 0.2s;
}

.finance-lesson-item:hover {
    background: var(--bg-secondary, #f3f4f6);
}

.finance-lesson-item.active {
    background: var(--primary-light, #dbeafe);
    color: var(--primary-color, #2563eb);
}

.finance-lesson-item .lesson-number {
    font-weight: 600;
    font-size: 0.85rem;
    color: var(--text-secondary, #6b7280);
    min-width: 24px;
}

.finance-lesson-item.active .lesson-number {
    color: var(--primary-color, #2563eb);
}

.finance-lesson-item .lesson-title {
    font-size: 0.9rem;
    flex: 1;
}

.finance-resizer {
    width: 4px;
    background: var(--border-color, #e5e7eb);
    cursor: col-resize;
    transition: background 0.2s;
}

.finance-resizer:hover,
.finance-resizer.resizing {
    background: var(--primary-color, #2563eb);
}

.finance-right {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.finance-lesson-placeholder {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: var(--text-secondary, #6b7280);
}

.finance-lesson-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.finance-lesson-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 20px;
    border-bottom: 1px solid var(--border-color, #e5e7eb);
    background: var(--bg-primary, #fff);
}

.finance-lesson-header h2 {
    margin: 0;
    font-size: 1.1rem;
    font-weight: 600;
}

.finance-lesson-actions {
    display: flex;
    align-items: center;
    gap: 8px;
}

.finance-lesson-actions .btn {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.finance-iframe-container {
    flex: 1;
    overflow: hidden;
}

.finance-iframe-container iframe {
    width: 100%;
    height: 100%;
    border: none;
}

/* =========================================================================
   GLOBAL OVERFLOW FIXES FOR LESSON PANELS
   Prevents content from overflowing when panel width is reduced
   ========================================================================= */

/* Left panels - prevent horizontal overflow */
.history-left,
.civics-left,
.economics-left,
.geography-left,
.sociology-left,
.arthistory-left,
.music-left,
.philosophy-left,
.linguistics-left,
.environment-left,
.cs-left,
.finance-left,
.languages-left,
.science-left,
.math-left,
.ela-left {
    overflow: hidden !important;
}

/* Nav content areas - prevent horizontal overflow */
.history-nav-content,
.civics-nav-content,
.economics-nav-content,
.geography-nav-content,
.sociology-nav-content,
.arthistory-nav-content,
.music-nav-content,
.philosophy-nav-content,
.linguistics-nav-content,
.environment-nav-content,
.cs-nav-content,
.finance-nav-content,
.languages-left,
.science-nav-content,
.math-nav-content,
.ela-nav-content {
    overflow-x: hidden !important;
}

/* Lesson lists - ensure they don't overflow */
.history-lesson-list,
.civics-lesson-list,
.economics-lesson-list,
.geography-lesson-list,
.sociology-lesson-list,
.arthistory-lesson-list,
.music-lesson-list,
.philosophy-lesson-list,
.linguistics-lesson-list,
.environment-lesson-list,
.cs-lesson-list,
.finance-lesson-list {
    overflow: hidden;
}

/* Lesson items - allow flex children to shrink properly */
.history-lesson-item,
.civics-lesson-item,
.economics-lesson-item,
.geography-lesson-item,
.sociology-lesson-item,
.arthistory-lesson-item,
.music-lesson-item,
.philosophy-lesson-item,
.linguistics-lesson-item,
.environment-lesson-item {
    min-width: 0 !important;
    overflow: hidden;
}

/* Lesson names - truncate with ellipsis when too long */
.history-lesson-item .lesson-name,
.civics-lesson-item .lesson-name,
.economics-lesson-item .lesson-name,
.geography-lesson-item .lesson-name,
.sociology-lesson-item .lesson-name,
.arthistory-lesson-item .lesson-name,
.music-lesson-item .lesson-name,
.philosophy-lesson-item .lesson-name,
.linguistics-lesson-item .lesson-name,
.environment-lesson-item .lesson-name {
    overflow: hidden !important;
    text-overflow: ellipsis !important;
    white-space: nowrap !important;
    min-width: 0 !important;
    flex: 1;
}

/* Nav content - constrain all children to panel width */
.history-nav-content *,
.civics-nav-content *,
.economics-nav-content *,
.geography-nav-content *,
.sociology-nav-content *,
.arthistory-nav-content *,
.music-nav-content *,
.philosophy-nav-content *,
.linguistics-nav-content * {
    max-width: 100% !important;
    box-sizing: border-box !important;
}

/* Course selector containers - prevent overflow */
.history-selector,
.civics-selector,
.economics-selector,
.geography-selector,
.sociology-selector,
.arthistory-selector,
.music-selector,
.philosophy-selector,
.linguistics-selector {
    overflow: hidden !important;
    width: 100% !important;
    max-width: 100% !important;
}

/* Course selector dropdowns - prevent overflow */
.history-selector select,
.civics-selector select,
.economics-selector select,
.geography-selector select,
.sociology-selector select,
.arthistory-selector select,
.music-selector select,
.philosophy-selector select,
.linguistics-selector select {
    width: 100% !important;
    max-width: 100% !important;
    box-sizing: border-box !important;
}

/* Right panels - z-index to stay above left panel overflow */
.history-right,
.civics-right,
.economics-right,
.geography-right,
.sociology-right,
.arthistory-right,
.music-right,
.philosophy-right {
    position: relative;
    z-index: 10;
}

/* Resizers - z-index to stay above left panel overflow */
.history-resizer,
.civics-resizer,
.economics-resizer,
.geography-resizer,
.sociology-resizer,
.arthistory-resizer,
.music-resizer,
.philosophy-resizer {
    position: relative;
    z-index: 10;
}

/* Target select dropdowns by ID - clip overflow */
#historyCourseSelect,
#civicsCourseSelect,
#economicsCourseSelect,
#geographyCourseSelect,
#sociologyCourseSelect,
#artHistoryCourseSelect,
#musicCourseSelect,
#philosophyCourseSelect {
    width: 100% !important;
    max-width: 100% !important;
    overflow: hidden !important;
    text-overflow: ellipsis !important;
    box-sizing: border-box !important;
}

/* Target nav content containers by ID */
#historyNavContent,
#civicsNavContent,
#economicsNavContent,
#geographyNavContent,
#sociologyNavContent,
#artHistoryNavContent,
#musicNavContent,
#philosophyNavContent {
    overflow: hidden !important;
}

/* Target left panels by ID - lower z-index so right panel covers overflow */
#historyLeft,
#civicsLeft,
#economicsLeft,
#geographyLeft,
#sociologyLeft,
#artHistoryLeft {
    overflow: hidden !important;
    overflow-x: hidden !important;
    position: relative;
    z-index: 1;
}
#musicLeft,
#philosophyLeft {
    overflow: hidden !important;
    position: relative;
    z-index: 1;
}

/* Right panels and resizers must be higher z-index to cover dropdown overflow */
#historyRight,
#civicsRight,
#economicsRight,
#geographyRight,
#sociologyRight,
#artHistoryRight,
#musicRight,
#philosophyRight,
#historyResizer,
#civicsResizer,
#economicsResizer,
#geographyResizer,
#sociologyResizer,
#artHistoryResizer,
#musicResizer,
#philosophyResizer {
    position: relative;
    z-index: 100;
}

/* Study Tools Header Buttons */
/* Study tools header styles moved to .history-lesson-actions section */

/* Simple Mind Map for Class Tools */
.mindmap-simple {
    padding: 20px;
}

.mindmap-simple .mindmap-center {
    text-align: center;
    font-size: 1.5rem;
    color: var(--primary-color);
    margin-bottom: 24px;
    padding: 16px;
    background: var(--bg-secondary);
    border-radius: 8px;
}

.mindmap-branches {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 16px;
}

.mindmap-branch {
    background: var(--bg-secondary);
    border-radius: 8px;
    padding: 16px;
    border-left: 4px solid var(--primary-color);
}

.mindmap-branch h4 {
    margin: 0 0 12px 0;
    color: var(--text-primary);
}

.mindmap-branch ul {
    margin: 0;
    padding-left: 20px;
}

.mindmap-branch li {
    margin-bottom: 6px;
    color: var(--text-secondary);
}

/* Study Guide Content */
.studyguide-content {
    padding: 20px;
}

.studyguide-content h3 {
    color: var(--primary-color);
    margin-bottom: 20px;
}

.studyguide-content h4 {
    color: var(--text-primary);
    margin: 20px 0 12px 0;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 8px;
}

.concepts-list {
    display: grid;
    gap: 12px;
}

.concepts-list dt {
    font-weight: 600;
    color: var(--text-primary);
}

.concepts-list dd {
    margin: 4px 0 0 0;
    color: var(--text-secondary);
    padding-left: 16px;
}

.key-points li, .takeaways li {
    margin-bottom: 8px;
    color: var(--text-secondary);
}

/* Summary Content */
.summary-content {
    padding: 20px;
}

.summary-content h3 {
    color: var(--primary-color);
    margin-bottom: 20px;
}

.summary-content h4 {
    color: var(--text-primary);
    margin: 20px 0 12px 0;
}

.summary-content p {
    color: var(--text-secondary);
    line-height: 1.6;
}

.summary-content ul {
    padding-left: 20px;
}

.summary-content li {
    margin-bottom: 8px;
    color: var(--text-secondary);
}