/* Reset et base */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header */
.header-main {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 0;
}

.logo-section {
    display: flex;
    align-items: center;
    gap: 15px;
    cursor: pointer;
    transition: transform 0.2s ease;
}

.logo-section:hover {
    transform: translateY(-2px);
}

.logo {
    font-size: 24px;
    font-weight: 700;
    color: #667eea;
    margin: 0;
}

.creator-signature {
    font-size: 14px;
    color: #666;
    font-style: italic;
    border-left: 2px solid #667eea;
    padding-left: 12px;
}

.header-nav {
    display: flex;
    align-items: center;
    gap: 15px;
}

.user-menu {
    display: flex;
    align-items: center;
    gap: 10px;
}

/* Boutons */
.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 500;
    text-decoration: none;
    display: inline-block;
    transition: all 0.3s ease;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
    background: transparent;
    color: #667eea;
    border: 2px solid #667eea;
    padding: 10px 22px;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 500;
    text-decoration: none;
    display: inline-block;
    transition: all 0.3s ease;
}

.btn-secondary:hover {
    background: #667eea;
    color: white;
    transform: translateY(-2px);
}

.btn-large {
    padding: 16px 32px;
    font-size: 18px;
}

.btn-nav {
    background: #667eea;
    color: white;
    border: none;
    padding: 10px 16px;
    border-radius: 6px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 8px;
    transition: all 0.3s ease;
}

.btn-nav:hover:not(:disabled) {
    background: #5a6fd8;
    transform: translateY(-1px);
}

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

.btn-close {
    background: none;
    border: none;
    font-size: 24px;
    cursor: pointer;
    color: #666;
    padding: 5px;
}

.btn-logout {
    background: #e74c3c;
    color: white;
    border: none;
    padding: 8px 16px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
}

/* Page d'accueil */
.welcome-page {
    min-height: calc(100vh - 80px);
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
}

.welcome-content h2 {
    font-size: 48px;
    font-weight: 700;
    color: white;
    margin-bottom: 20px;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.welcome-content p {
    font-size: 20px;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 40px;
    max-width: 600px;
}

.welcome-actions {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
}

/* Modals */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(5px);
}

.modal-content {
    background: white;
    margin: 10% auto;
    padding: 30px;
    border-radius: 12px;
    width: 90%;
    max-width: 400px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
}

.modal-content h2 {
    text-align: center;
    margin-bottom: 25px;
    color: #333;
}

.modal-content input {
    width: 100%;
    padding: 12px;
    margin-bottom: 15px;
    border: 2px solid #e1e8ed;
    border-radius: 8px;
    font-size: 16px;
    transition: border-color 0.3s ease;
}

.modal-content input:focus {
    outline: none;
    border-color: #667eea;
}

.modal-content button {
    width: 100%;
    margin-top: 10px;
}

.modal-content p {
    text-align: center;
    margin-top: 20px;
}

.modal-content a {
    color: #667eea;
    text-decoration: none;
}

.close {
    color: #aaa;
    float: right;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.close:hover {
    color: #000;
}

/* Sommaire des cours */
.course-summary {
    padding: 40px 0;
    background: rgba(255, 255, 255, 0.95);
    min-height: calc(100vh - 80px);
}

.course-summary h2 {
    text-align: center;
    font-size: 36px;
    margin-bottom: 40px;
    color: #333;
}

.modules-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
    max-width: 1200px;
    margin: 0 auto;
}

.module-card {
    background: white;
    border-radius: 12px;
    padding: 25px;
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.module-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.module-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
}

.module-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 15px;
}

.module-number {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 6px 12px;
    border-radius: 20px;
    font-weight: 600;
    font-size: 14px;
}

.module-icon {
    font-size: 24px;
    color: #667eea;
}

.module-card h3 {
    font-size: 20px;
    margin-bottom: 10px;
    color: #333;
    line-height: 1.3;
}

.module-card p {
    color: #666;
    margin-bottom: 20px;
    font-size: 14px;
}

.module-progress {
    margin-bottom: 15px;
}

.progress-bar {
    background: #e1e8ed;
    height: 8px;
    border-radius: 4px;
    overflow: hidden;
    margin-bottom: 8px;
}

.progress-fill {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    height: 100%;
    width: 0%;
    transition: width 0.3s ease;
}

.progress-text {
    font-size: 12px;
    color: #666;
    font-weight: 500;
}

.module-info {
    display: flex;
    justify-content: space-between;
    font-size: 12px;
    color: #888;
}

.module-info span {
    display: flex;
    align-items: center;
    gap: 4px;
}

/* Interface de cours */
.course-interface {
    background: white;
    min-height: 100vh;
}

.course-layout {
    display: flex;
    height: calc(100vh - 80px);
}

.course-sidebar {
    width: 300px;
    background: #f8f9fa;
    border-right: 1px solid #e1e8ed;
    overflow-y: auto;
}

.sidebar-header {
    padding: 20px;
    border-bottom: 1px solid #e1e8ed;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.sidebar-header h3 {
    color: #333;
    font-size: 18px;
}

.sidebar-content {
    padding: 20px;
}

.chapter-nav-item {
    background: white;
    border: 1px solid #e1e8ed;
    border-radius: 8px;
    padding: 12px;
    margin-bottom: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.chapter-nav-item:hover {
    border-color: #667eea;
    box-shadow: 0 2px 8px rgba(102, 126, 234, 0.1);
}

.chapter-nav-item.active {
    background: #667eea;
    color: white;
    border-color: #667eea;
}

.chapter-nav-item.completed {
    border-color: #28a745;
    background: #f8fff9;
}

.chapter-nav-item.completed .chapter-status {
    color: #28a745;
}

.chapter-title {
    font-weight: 500;
    font-size: 14px;
}

.chapter-status {
    font-size: 12px;
    color: #666;
}

.sidebar-progress {
    margin-top: 30px;
    padding-top: 20px;
    border-top: 1px solid #e1e8ed;
}

.sidebar-progress h4 {
    margin-bottom: 15px;
    color: #333;
    font-size: 16px;
}

.course-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.course-header {
    padding: 20px 30px;
    border-bottom: 1px solid #e1e8ed;
    background: white;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.breadcrumb {
    color: #666;
    font-size: 14px;
}

.breadcrumb span {
    margin: 0 5px;
}

.course-actions {
    display: flex;
    gap: 10px;
}

.course-content {
    flex: 1;
    padding: 30px;
    overflow-y: auto;
    background: #fafbfc;
}

#page-content {
    background: white;
    padding: 40px;
    border-radius: 12px;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
    max-width: 800px;
    margin: 0 auto;
}

.course-navigation {
    padding: 20px 30px;
    background: white;
    border-top: 1px solid #e1e8ed;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

#page-indicator {
    color: #666;
    font-weight: 500;
}

/* Notes panel */
.notes-panel {
    width: 300px;
    background: white;
    border-left: 1px solid #e1e8ed;
    display: flex;
    flex-direction: column;
}

.notes-header {
    padding: 20px;
    border-bottom: 1px solid #e1e8ed;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.notes-header h4 {
    color: #333;
}

.notes-content {
    flex: 1;
    padding: 20px;
    display: flex;
    flex-direction: column;
}

#notes-text {
    flex: 1;
    border: 1px solid #e1e8ed;
    border-radius: 8px;
    padding: 15px;
    resize: none;
    font-family: inherit;
    margin-bottom: 15px;
}

/* Quiz interface */
.quiz-interface {
    background: rgba(255, 255, 255, 0.95);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
}

.quiz-container {
    background: white;
    border-radius: 12px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15);
    width: 90%;
    max-width: 800px;
    padding: 30px;
}

.quiz-header {
    text-align: center;
    margin-bottom: 40px;
    padding-bottom: 20px;
    border-bottom: 1px solid #e1e8ed;
}

.quiz-header h2 {
    color: #333;
    margin-bottom: 20px;
}

.quiz-progress {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
}

#quiz-progress-text {
    color: #666;
    font-weight: 500;
}

.quiz-content h3 {
    margin-bottom: 25px;
    color: #333;
    font-size: 20px;
    line-height: 1.5;
}

.quiz-answer {
    background: #f8f9fa;
    border: 2px solid #e1e8ed;
    border-radius: 8px;
    padding: 15px 20px;
    margin-bottom: 15px;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 15px;
}

.quiz-answer:hover {
    border-color: #667eea;
    background: #f0f4ff;
}

.quiz-answer.selected {
    border-color: #667eea;
    background: #667eea;
    color: white;
}

.quiz-answer.correct {
    border-color: #28a745;
    background: #d4edda;
    color: #155724;
}

.quiz-answer.incorrect {
    border-color: #dc3545;
    background: #f8d7da;
    color: #721c24;
}

.answer-letter {
    background: #667eea;
    color: white;
    width: 30px;
    height: 30px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 14px;
}

.quiz-answer.selected .answer-letter {
    background: white;
    color: #667eea;
}

.quiz-feedback {
    background: #f8f9fa;
    border-radius: 8px;
    padding: 20px;
    margin-top: 20px;
}

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

.quiz-results h3 {
    margin-bottom: 20px;
    color: #333;
}

.score-display {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 20px;
    border-radius: 12px;
    margin: 20px 0;
    font-size: 24px;
    font-weight: 600;
}

.quiz-certificate {
    background: #d4edda;
    border: 1px solid #c3e6cb;
    border-radius: 8px;
    padding: 20px;
    margin: 20px 0;
}

.quiz-certificate h4 {
    color: #155724;
    margin-bottom: 10px;
}

/* Contenu des pages */
.page-content h1 {
    color: #333;
    font-size: 28px;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 3px solid #667eea;
}

.page-content h2 {
    color: #444;
    font-size: 22px;
    margin: 25px 0 15px 0;
}

.page-content h3 {
    color: #555;
    font-size: 18px;
    margin: 20px 0 10px 0;
}

.page-content p {
    margin-bottom: 15px;
    line-height: 1.7;
    color: #555;
}

.page-content ul, .page-content ol {
    margin: 15px 0;
    padding-left: 25px;
}

.page-content li {
    margin-bottom: 8px;
    line-height: 1.6;
}

.highlight-box {
    background: linear-gradient(135deg, #f8f9ff 0%, #e8f0ff 100%);
    border-left: 4px solid #667eea;
    padding: 20px;
    margin: 20px 0;
    border-radius: 0 8px 8px 0;
}

.example-box {
    background: #f8fff9;
    border: 1px solid #c3e6cb;
    border-radius: 8px;
    padding: 20px;
    margin: 20px 0;
}

.example-box h4 {
    color: #155724;
    margin-bottom: 10px;
}

.warning-box {
    background: #fff3cd;
    border: 1px solid #ffeaa7;
    border-radius: 8px;
    padding: 20px;
    margin: 20px 0;
}

.warning-box h4 {
    color: #856404;
    margin-bottom: 10px;
}

.code-block {
    background: #2d3748;
    color: #e2e8f0;
    padding: 20px;
    border-radius: 8px;
    font-family: 'Courier New', monospace;
    margin: 15px 0;
    overflow-x: auto;
}

.key-points {
    background: #e8f5e8;
    border-radius: 8px;
    padding: 20px;
    margin: 20px 0;
}

.key-points h4 {
    color: #2d5a2d;
    margin-bottom: 15px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.key-points ul {
    list-style: none;
    padding-left: 0;
}

.key-points li {
    padding: 8px 0;
    position: relative;
    padding-left: 25px;
}

.key-points li::before {
    content: '✓';
    position: absolute;
    left: 0;
    top: 8px;
    color: #28a745;
    font-weight: bold;
}

/* Styles pour l'administration */
.admin-container {
    padding: 20px 0;
    background: #f8f9fa;
    min-height: calc(100vh - 80px);
}

.admin-tabs {
    display: flex;
    gap: 10px;
    margin-bottom: 30px;
    border-bottom: 2px solid #e1e8ed;
    overflow-x: auto;
}

.admin-tab {
    background: none;
    border: none;
    padding: 15px 20px;
    color: #666;
    cursor: pointer;
    font-weight: 500;
    border-bottom: 3px solid transparent;
    transition: all 0.3s ease;
    white-space: nowrap;
}

.admin-tab:hover {
    color: #667eea;
    background: rgba(102, 126, 234, 0.1);
}

.admin-tab.active {
    color: #667eea;
    border-bottom-color: #667eea;
    background: rgba(102, 126, 234, 0.1);
}

.admin-tab-content {
    display: none;
    animation: fadeIn 0.3s ease;
}

.admin-tab-content.active {
    display: block;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* Statistiques */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.stat-card {
    background: white;
    padding: 25px;
    border-radius: 12px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    display: flex;
    align-items: center;
    gap: 20px;
}

.stat-icon {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    width: 60px;
    height: 60px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
}

.stat-content h3 {
    font-size: 32px;
    font-weight: 700;
    color: #333;
    margin: 0;
}

.stat-content p {
    color: #666;
    margin: 5px 0 0 0;
    font-size: 14px;
}

/* Graphiques */
.charts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.chart-card {
    background: white;
    padding: 25px;
    border-radius: 12px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.chart-card h3 {
    margin-bottom: 20px;
    color: #333;
}

/* Étudiants récents */
.recent-students {
    background: white;
    padding: 25px;
    border-radius: 12px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.recent-students h3 {
    margin-bottom: 20px;
    color: #333;
}

.recent-student-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 0;
    border-bottom: 1px solid #f0f0f0;
}

.recent-student-item:last-child {
    border-bottom: none;
}

.student-info h4 {
    margin: 0 0 5px 0;
    color: #333;
}

.student-info p {
    margin: 0 0 5px 0;
    color: #666;
    font-size: 14px;
}

.student-info small {
    color: #999;
    font-size: 12px;
}

.progress-circle {
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: 600;
    font-size: 14px;
}

/* Table des étudiants */
.students-controls {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    gap: 20px;
    flex-wrap: wrap;
}

.search-box {
    position: relative;
    flex: 1;
    max-width: 300px;
}

.search-box i {
    position: absolute;
    left: 15px;
    top: 50%;
    transform: translateY(-50%);
    color: #666;
}

.search-box input {
    width: 100%;
    padding: 12px 15px 12px 45px;
    border: 2px solid #e1e8ed;
    border-radius: 8px;
    font-size: 14px;
}

.search-box input:focus {
    outline: none;
    border-color: #667eea;
}

.filter-controls {
    display: flex;
    gap: 10px;
}

.filter-controls select {
    padding: 12px 15px;
    border: 2px solid #e1e8ed;
    border-radius: 8px;
    font-size: 14px;
    background: white;
}

.students-table {
    background: white;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.students-table table {
    width: 100%;
    border-collapse: collapse;
}

.students-table th,
.students-table td {
    padding: 15px;
    text-align: left;
    border-bottom: 1px solid #f0f0f0;
}

.students-table th {
    background: #f8f9fa;
    font-weight: 600;
    color: #333;
}

.btn-view, .btn-reset {
    background: none;
    border: none;
    padding: 8px;
    margin: 0 2px;
    cursor: pointer;
    border-radius: 4px;
    transition: background 0.3s ease;
}

.btn-view {
    color: #667eea;
}

.btn-view:hover {
    background: rgba(102, 126, 234, 0.1);
}

.btn-reset {
    color: #e74c3c;
}

.btn-reset:hover {
    background: rgba(231, 76, 60, 0.1);
}

.btn-danger {
    background: #e74c3c;
    color: white;
    border: none;
    padding: 12px 20px;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 500;
    transition: background 0.3s ease;
}

.btn-danger:hover {
    background: #c0392b;
}

/* Analytics */
.analytics-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.analytics-card {
    background: white;
    padding: 25px;
    border-radius: 12px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.analytics-card h3 {
    margin-bottom: 20px;
    color: #333;
}

.detailed-metrics {
    background: white;
    padding: 25px;
    border-radius: 12px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.detailed-metrics h3 {
    margin-bottom: 20px;
    color: #333;
}

.metrics-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 15px;
}

.metric-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px;
    background: #f8f9fa;
    border-radius: 8px;
}

.metric-item label {
    font-weight: 500;
    color: #333;
}

.metric-item span {
    font-weight: 600;
    color: #667eea;
}

/* Gestion de contenu */
.content-overview, .student-feedback {
    background: white;
    padding: 25px;
    border-radius: 12px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    margin-bottom: 20px;
}

.module-overview-item {
    padding: 20px;
    border: 1px solid #e1e8ed;
    border-radius: 8px;
    margin-bottom: 15px;
}

.module-overview-item h4 {
    margin-bottom: 10px;
    color: #333;
}

.module-overview-item p {
    color: #666;
    margin-bottom: 10px;
}

.module-stats {
    display: flex;
    gap: 20px;
}

.module-stats span {
    font-size: 14px;
    color: #999;
}

/* Paramètres */
.settings-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 20px;
}

.settings-section {
    background: white;
    padding: 25px;
    border-radius: 12px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.settings-section h3 {
    margin-bottom: 20px;
    color: #333;
}

.setting-item {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 15px;
}

.setting-item label {
    flex: 1;
    font-weight: 500;
    color: #333;
}

.setting-item input {
    padding: 8px 12px;
    border: 2px solid #e1e8ed;
    border-radius: 6px;
}

.setting-item input[type="checkbox"] {
    width: 20px;
    height: 20px;
}

.no-data, .no-feedback {
    text-align: center;
    color: #999;
    font-style: italic;
    padding: 40px;
}

/* Navigation des pages dans le cours */
.chapter-header {
    background: #f8f9fa;
    padding: 12px 15px;
    border-radius: 8px;
    margin-bottom: 10px;
    border-left: 4px solid #667eea;
}

.chapter-header h4 {
    margin: 0 0 5px 0;
    color: #333;
    font-size: 16px;
}

.chapter-pages {
    font-size: 12px;
    color: #666;
}

.page-nav-item {
    background: white;
    border: 1px solid #e1e8ed;
    border-radius: 6px;
    padding: 10px 15px;
    margin-bottom: 5px;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.page-nav-item:hover {
    border-color: #667eea;
    box-shadow: 0 2px 8px rgba(102, 126, 234, 0.1);
}

.page-nav-item.active {
    background: #667eea;
    color: white;
    border-color: #667eea;
}

.page-nav-item.completed {
    border-color: #28a745;
    background: #f8fff9;
}

.page-nav-item.completed .page-status {
    color: #28a745;
}

.page-title {
    font-size: 14px;
    font-weight: 500;
}

.page-status {
    font-size: 12px;
}

.page-status i {
    font-size: 10px;
}

/* Responsive */
@media (max-width: 768px) {
    .course-layout {
        flex-direction: column;
    }
    
    .course-sidebar {
        width: 100%;
        height: auto;
        max-height: 300px;
        overflow-y: auto;
    }
    
    .notes-panel {
        width: 100%;
        height: 300px;
    }
    
    .modules-grid {
        grid-template-columns: 1fr;
    }
    
    .welcome-content h2 {
        font-size: 32px;
    }
    
    .welcome-actions {
        flex-direction: column;
        align-items: center;
    }
    
    .logo-section {
        flex-direction: column;
        align-items: flex-start;
        gap: 5px;
    }
    
    .creator-signature {
        border-left: none;
        border-top: 2px solid #667eea;
        padding-left: 0;
        padding-top: 5px;
        font-size: 12px;
    }
    
    .header-content {
        flex-direction: column;
        gap: 15px;
        text-align: center;
    }
    
    .course-navigation {
        flex-wrap: wrap;
        gap: 10px;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .charts-grid {
        grid-template-columns: 1fr;
    }
    
    .students-controls {
        flex-direction: column;
        align-items: stretch;
    }
    
    .search-box {
        max-width: none;
    }
    
    .filter-controls {
        flex-wrap: wrap;
    }
    
    .settings-grid {
        grid-template-columns: 1fr;
    }
    
    .admin-tabs {
        flex-wrap: wrap;
    }
    
    .analytics-grid {
        grid-template-columns: 1fr;
    }
    
    .metrics-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .modal-content {
        margin: 5% auto;
        padding: 20px;
    }
    
    .course-content {
        padding: 20px;
    }
    
    #page-content {
        padding: 25px;
    }
    
    .admin-container {
        padding: 15px 0;
    }
    
    .stat-card {
        padding: 20px;
        flex-direction: column;
        text-align: center;
    }
    
    .recent-student-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 10px;
    }
    
    .students-table {
        overflow-x: auto;
    }
    
    .students-table table {
        min-width: 600px;
    }
}