/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --purple-50: #faf5ff;
    --purple-100: #f3e8ff;
    --purple-200: #e9d5ff;
    --purple-300: #d8b4fe;
    --purple-400: #c084fc;
    --purple-500: #a855f7;
    --purple-600: #9333ea;
    --purple-700: #7e22ce;
    --purple-800: #6b21a8;
    --purple-900: #581c87;
    
    --glass-bg: rgba(255, 255, 255, 0.1);
    --glass-border: rgba(255, 255, 255, 0.2);
    --glass-shadow: rgba(0, 0, 0, 0.1);
    
    --text-primary: #1e1b2e;
    --text-secondary: #6b7280;
    --text-muted: #9ca3af;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 25%, #a855f7 50%, #9333ea 75%, #7e22ce 100%);
    min-height: 100vh;
    color: var(--text-primary);
    line-height: 1.6;
}

/* Glassmorphic Card Styles */
.glass-card {
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 20px;
    box-shadow: 0 8px 32px 0 rgba(31, 38, 135, 0.37);
    padding: 2rem;
    transition: all 0.3s ease;
}

.glass-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 12px 40px 0 rgba(31, 38, 135, 0.5);
    border-color: rgba(255, 255, 255, 0.3);
}

/* Page Management */
.page {
    display: none;
    min-height: 100vh;
}

.page.active {
    display: block;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* Login Page */
.login-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 2rem;
}

.login-card {
    width: 100%;
    max-width: 450px;
    text-align: center;
}

.logo-container {
    margin-bottom: 1.5rem;
}

.logo {
    width: 80px;
    height: 80px;
    margin: 0 auto;
    background: linear-gradient(135deg, var(--purple-500), var(--purple-700));
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    font-weight: bold;
    color: white;
    box-shadow: 0 8px 24px rgba(168, 85, 247, 0.4);
}

.logo-small {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--purple-500), var(--purple-700));
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    font-weight: bold;
    color: white;
    flex-shrink: 0;
}

.login-title {
    font-size: 2rem;
    font-weight: 700;
    color: white;
    margin-bottom: 0.5rem;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

.login-subtitle {
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 2rem;
    font-size: 0.95rem;
}

.login-form {
    margin-bottom: 1.5rem;
}

.login-footer {
    margin-top: 1.5rem;
}

.login-note {
    font-size: 0.75rem;
    color: rgba(255, 255, 255, 0.7);
    margin-top: 1rem;
}

/* Form Elements */
.form-group {
    margin-bottom: 1.5rem;
    text-align: left;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: rgba(255, 255, 255, 0.95);
    font-size: 0.9rem;
}

.input-field,
.textarea-field {
    width: 100%;
    padding: 0.75rem 1rem;
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 12px;
    color: white;
    font-size: 1rem;
    transition: all 0.3s ease;
}

.input-field::placeholder,
.textarea-field::placeholder {
    color: rgba(255, 255, 255, 0.6);
}

.input-field:focus,
.textarea-field:focus {
    outline: none;
    background: rgba(255, 255, 255, 0.25);
    border-color: rgba(255, 255, 255, 0.5);
    box-shadow: 0 0 0 3px rgba(168, 85, 247, 0.3);
}

.textarea-field {
    resize: vertical;
    min-height: 100px;
    font-family: inherit;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    font-size: 0.95rem;
    font-weight: 500;
    border-radius: 12px;
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    font-family: inherit;
}

.btn-primary {
    background: linear-gradient(135deg, var(--purple-500), var(--purple-700));
    color: white;
    box-shadow: 0 4px 15px rgba(168, 85, 247, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(168, 85, 247, 0.6);
}

.btn-outline {
    background: rgba(255, 255, 255, 0.1);
    color: white;
    border: 1px solid rgba(255, 255, 255, 0.3);
    backdrop-filter: blur(10px);
}

.btn-outline:hover {
    background: rgba(255, 255, 255, 0.2);
    border-color: rgba(255, 255, 255, 0.4);
}

.btn-ghost {
    background: transparent;
    color: white;
    border: none;
}

.btn-ghost:hover {
    background: rgba(255, 255, 255, 0.1);
}

.btn-success {
    background: linear-gradient(135deg, #10b981, #059669);
    color: white;
    box-shadow: 0 4px 15px rgba(16, 185, 129, 0.4);
}

.btn-success:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(16, 185, 129, 0.6);
}

.btn-danger {
    background: linear-gradient(135deg, #ef4444, #dc2626);
    color: white;
}

.btn-danger:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(239, 68, 68, 0.4);
}

.btn-full {
    width: 100%;
}

.btn-back {
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
}

.icon {
    width: 1.25rem;
    height: 1.25rem;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
}

/* Header */
.header {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.2);
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.sticky-header {
    position: sticky;
    top: 0;
    z-index: 100;
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 1rem;
}

.header-logo {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.header-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: white;
    margin: 0;
}

.header-subtitle {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.8);
    margin: 0;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

/* Main Content */
.main-content {
    padding: 2rem 0;
    min-height: calc(100vh - 80px);
}

.page-header {
    margin-bottom: 2rem;
}

.page-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: white;
    margin-bottom: 0.5rem;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

.page-subtitle {
    font-size: 1.1rem;
    color: rgba(255, 255, 255, 0.9);
}

/* Courses Grid */
.courses-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.course-card {
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 20px;
    padding: 1.5rem;
    transition: all 0.3s ease;
    cursor: pointer;
    color: white;
}

.course-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 40px 0 rgba(31, 38, 135, 0.5);
    border-color: rgba(255, 255, 255, 0.3);
}

.course-card-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
    color: white;
    line-height: 1.3;
}

.course-card-description {
    color: rgba(255, 255, 255, 0.85);
    margin-bottom: 1.5rem;
    font-size: 0.95rem;
    line-height: 1.6;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.course-card-stats {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    margin-bottom: 1rem;
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.8);
}

.course-card-stat {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.progress-section {
    margin: 1rem 0;
}

.progress-header {
    display: flex;
    justify-content: space-between;
    margin-bottom: 0.5rem;
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.8);
}

.progress-bar-container {
    width: 100%;
    height: 8px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 10px;
    overflow: hidden;
    margin-bottom: 1rem;
}

.progress-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--purple-400), var(--purple-600));
    border-radius: 10px;
    transition: width 0.3s ease;
    box-shadow: 0 2px 8px rgba(168, 85, 247, 0.4);
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 4rem 2rem;
    color: white;
}

.empty-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 1.5rem;
    opacity: 0.6;
}

.empty-state h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
    color: white;
}

.empty-state p {
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 1.5rem;
}

/* Error Message */
.error-message {
    background: rgba(239, 68, 68, 0.2);
    border: 1px solid rgba(239, 68, 68, 0.4);
    color: white;
    padding: 0.75rem 1rem;
    border-radius: 12px;
    margin-bottom: 1rem;
    font-size: 0.9rem;
    backdrop-filter: blur(10px);
}

/* Chapter Content */
.chapter-content {
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 20px;
    padding: 2rem;
    margin-bottom: 2rem;
    color: white;
}

.chapter-content h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: white;
}

.chapter-content h2 {
    font-size: 2rem;
    font-weight: 600;
    margin-top: 2rem;
    margin-bottom: 1rem;
    color: white;
}

.chapter-content h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-top: 1.5rem;
    margin-bottom: 0.75rem;
    color: white;
}

.chapter-content p {
    margin-bottom: 1rem;
    line-height: 1.8;
    color: rgba(255, 255, 255, 0.9);
}

.chapter-content ul,
.chapter-content ol {
    margin-left: 1.5rem;
    margin-bottom: 1rem;
    color: rgba(255, 255, 255, 0.9);
}

.chapter-content li {
    margin-bottom: 0.5rem;
}

.chapter-content code {
    background: rgba(0, 0, 0, 0.2);
    padding: 0.2rem 0.5rem;
    border-radius: 6px;
    font-family: 'Courier New', monospace;
    font-size: 0.9em;
}

.chapter-content pre {
    background: rgba(0, 0, 0, 0.2);
    padding: 1rem;
    border-radius: 12px;
    overflow-x: auto;
    margin-bottom: 1rem;
}

.chapter-content pre code {
    background: none;
    padding: 0;
}

.chapter-content strong {
    font-weight: 600;
    color: white;
}

.chapter-content a {
    color: var(--purple-300);
    text-decoration: underline;
}

.chapter-content a:hover {
    color: var(--purple-200);
}

/* Video Container */
.video-container {
    width: 100%;
    aspect-ratio: 16 / 9;
    background: rgba(0, 0, 0, 0.3);
    border-radius: 16px;
    overflow: hidden;
    margin-bottom: 2rem;
}

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

/* Chapter Navigation */
.chapter-navigation {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 2rem;
    flex-wrap: wrap;
    gap: 1rem;
}

.chapter-complete-badge {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    background: rgba(16, 185, 129, 0.2);
    border: 1px solid rgba(16, 185, 129, 0.4);
    color: #10b981;
    padding: 0.5rem 1rem;
    border-radius: 12px;
    font-weight: 500;
    backdrop-filter: blur(10px);
}

/* Form Card */
.form-card {
    margin-bottom: 2rem;
}

.form-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: white;
    margin-bottom: 0.5rem;
}

.form-subtitle {
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: 1.5rem;
    font-size: 0.95rem;
}

.course-form {
    margin-top: 1.5rem;
}

.form-actions {
    display: flex;
    gap: 1rem;
    margin-top: 1.5rem;
}

/* Course Stats */
.course-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1rem;
    margin-top: 1.5rem;
}

.course-stat {
    text-align: center;
    padding: 1rem;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 12px;
}

.course-stat-value {
    font-size: 2rem;
    font-weight: 700;
    color: white;
    margin-bottom: 0.25rem;
}

.course-stat-label {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.8);
}

/* Chapter List */
.chapter-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.chapter-item {
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 16px;
    padding: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
    transition: all 0.3s ease;
    cursor: pointer;
}

.chapter-item:hover {
    transform: translateX(4px);
    border-color: rgba(255, 255, 255, 0.3);
    box-shadow: 0 8px 24px rgba(31, 38, 135, 0.3);
}

.chapter-item-info {
    display: flex;
    align-items: center;
    gap: 1rem;
    flex: 1;
}

.chapter-number {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.2);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    color: white;
    flex-shrink: 0;
}

.chapter-item.completed .chapter-number {
    background: rgba(16, 185, 129, 0.3);
    color: #10b981;
}

.chapter-item-details h3 {
    font-size: 1.25rem;
    font-weight: 600;
    color: white;
    margin-bottom: 0.25rem;
}

.chapter-item-meta {
    display: flex;
    align-items: center;
    gap: 1rem;
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.8);
}

/* Loading Spinner */
.loading-spinner {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(10px);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    color: white;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 1rem;
}

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

/* Badge */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 0.25rem 0.75rem;
    border-radius: 12px;
    font-size: 0.75rem;
    font-weight: 500;
}

.badge-published {
    background: rgba(16, 185, 129, 0.2);
    color: #10b981;
    border: 1px solid rgba(16, 185, 129, 0.3);
}

.badge-draft {
    background: rgba(251, 191, 36, 0.2);
    color: #fbbf24;
    border: 1px solid rgba(251, 191, 36, 0.3);
}

/* Admin Actions */
.admin-actions {
    display: flex;
    gap: 0.5rem;
}

.btn-icon {
    padding: 0.5rem;
    min-width: auto;
}

/* Responsive Design */
@media (max-width: 768px) {
    .page-title {
        font-size: 2rem;
    }
    
    .courses-grid {
        grid-template-columns: 1fr;
    }
    
    .header-content {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .header-actions {
        width: 100%;
        justify-content: flex-end;
    }
    
    .chapter-navigation {
        flex-direction: column;
    }
    
    .form-actions {
        flex-direction: column;
    }
    
    .chapter-item {
        flex-direction: column;
        align-items: flex-start;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 1rem;
    }
    
    .login-card {
        padding: 1.5rem;
    }
    
    .glass-card {
        padding: 1.5rem;
    }
    
    .page-title {
        font-size: 1.75rem;
    }
}