#app{min-height:100vh}:root{--primary-color: #1a4d6f;--primary-hover: #0f3450;--accent-color: #ff6b35;--accent-hover: #e55a26;--secondary-color: #2c3e50;--success-color: #27ae60;--danger-color: #dc3545;--warning-color: #ffc107;--info-color: #17a2b8;--light-color: #f5f5f5;--dark-color: #2c3e50;--text-color: #333;--border-color: #ddd;--bg-primary: #ffffff;--bg-secondary: #f8f9fa;--bg-surface: #ffffff;--text-primary: #333;--text-secondary: #666;--navbar-bg: #1a4d6f;--footer-bg: #f8f9fa;--card-bg: #ffffff;--card-border: #e8e8e8;--border-radius: 8px;--transition: all .3s ease;--box-shadow-sm: 0 2px 4px rgba(0, 0, 0, .1);--box-shadow-md: 0 2px 8px rgba(0, 0, 0, .1);--box-shadow-lg: 0 4px 16px rgba(0, 0, 0, .15);--spacing-xs: .5rem;--spacing-sm: 1rem;--spacing-md: 1.5rem;--spacing-lg: 2rem;--spacing-xl: 3rem}html.dark{--primary-color: #60a5fa;--primary-hover: #3b82f6;--accent-color: #60a5fa;--accent-hover: #3b82f6;--text-color: #e2e8f0;--border-color: #334155;--bg-primary: #0f172a;--bg-secondary: #1e293b;--bg-surface: #1e293b;--text-primary: #e2e8f0;--text-secondary: #94a3b8;--navbar-bg: #0f172a;--footer-bg: #1e293b;--card-bg: #1e293b;--card-border: #334155;--light-color: #1e293b;--dark-color: #0f172a}html.dark body{background:var(--bg-primary);color:var(--text-primary)}html.dark .card,html.dark .panel,html.dark .page-card,html.dark .lesson-card,html.dark .lesson-item,html.dark .certificate-card,html.dark .progress-card,html.dark .stat-card,html.dark .info-card,html.dark .feature-card,html.dark .pricing-card,html.dark .quiz-card,html.dark .quiz-container,html.dark .question-card,html.dark .step-card,html.dark .checkout-card,html.dark .order-card,html.dark .profile-card,html.dark .settings-card,html.dark .notification-card,html.dark .subscription-card,html.dark .badge-card,html.dark .auth-card,html.dark .form-card,html.dark .hero-card,html.dark .about-card,html.dark .contact-card,html.dark [class*=-card],html.dark [class*=-panel],html.dark [class*=-box],html.dark [class*=-section]:not(section){background:var(--card-bg);border-color:var(--card-border);color:var(--text-primary)}html.dark .lessons-header h1{color:#fff!important}html.dark .lessons-header p{color:#94a3b8!important}html.dark .title-section,html.dark .lesson-detail .title-section{background:transparent!important;border-color:transparent!important;box-shadow:none!important}html.dark input,html.dark textarea,html.dark select,html.dark .form-control,html.dark .input-field,html.dark [class*=input]{background:#1e293b;color:var(--text-primary);border-color:var(--border-color)}html.dark input::placeholder,html.dark textarea::placeholder{color:var(--text-secondary)}html.dark table,html.dark th,html.dark td{border-color:var(--border-color)}html.dark th{background:#293548;color:var(--text-primary)}html.dark tr:nth-child(2n){background:#1a2438}html.dark .modal,html.dark .modal-content,html.dark [class*=modal]{background:var(--card-bg);color:var(--text-primary);border-color:var(--card-border)}html.dark .badge,html.dark .tag,html.dark .pill,html.dark [class*=badge]:not(.badge-card),html.dark [class*=tag],html.dark [class*=chip]{background:#293548;color:var(--text-primary)}html.dark h1,html.dark h2,html.dark h3,html.dark h4,html.dark h5,html.dark h6,html.dark p{color:var(--text-primary)}html.dark hr,html.dark .divider,html.dark [class*=divider],html.dark [class*=separator]{border-color:var(--border-color);background:var(--border-color)}html.dark .alert,html.dark .notice,html.dark .info-box,html.dark .warning-box,html.dark .success-box,html.dark .error-box,html.dark [class*=alert],html.dark [class*=notice],html.dark [class*=banner]:not(.navbar){background:#1e293b;border-color:var(--border-color);color:var(--text-primary)}html.dark .list-item,html.dark [class*=list-item],html.dark [class*=list-row]{background:var(--card-bg);border-color:var(--card-border);color:var(--text-primary)}html.dark .tab,html.dark .tabs,html.dark [class*=-tab],html.dark [class*=tab-]{color:var(--text-secondary);border-color:var(--border-color)}html.dark .tab.active,html.dark [class*=tab].active,html.dark [class*=tab-].active{color:var(--text-primary);border-color:var(--primary-color)}html.dark .progress,html.dark .progress-bar,html.dark [class*=progress-track],html.dark [class*=progress-bg]{background:#293548}html.dark .sidebar,html.dark [class*=sidebar]{background:#0f172a;border-color:var(--border-color)}html.dark [class*=skeleton],html.dark [class*=loading]{background:#293548}html.dark .page-header,html.dark .hero,html.dark [class*=page-header],html.dark [class*=hero-section],html.dark [class*=hero-content]{background:var(--bg-primary);color:var(--text-primary)}html.dark .container,html.dark .wrapper,html.dark .content,html.dark [class*=-container],html.dark [class*=-wrapper],html.dark [class*=-content]:not(.main-content){background:transparent;color:var(--text-primary)}html.dark .text-secondary,html.dark .subtitle,html.dark .description,html.dark .meta,html.dark small,html.dark [class*=subtitle],html.dark [class*=description],html.dark [class*=caption],html.dark [class*=hint],html.dark [class*=label]{color:var(--text-secondary)}html.dark a:not(.btn):not(.nav-link):not(.dropdown-item):not(.router-link-active){color:var(--primary-color)}html.dark .btn-outline,html.dark .btn-ghost,html.dark [class*=btn-outline],html.dark [class*=btn-ghost]{background:transparent;color:var(--text-primary);border-color:var(--border-color)}html.dark .btn-outline:hover,html.dark .btn-ghost:hover,html.dark [class*=btn-outline]:hover,html.dark [class*=btn-ghost]:hover{background:#293548}html.dark .dropdown,html.dark [class*=dropdown-menu]{background:#1e293b;border-color:var(--card-border)}html.dark [class*=dropdown-item]:hover{background:#293548}html.dark code,html.dark pre{background:#0f172a;color:#e2e8f0;border-color:var(--border-color)}*{margin:0;padding:0;box-sizing:border-box}html,body{width:100%;height:100%}body{font-family:Segoe UI,Tahoma,Geneva,Verdana,sans-serif;font-size:1rem;line-height:1.6;color:var(--text-primary);background-color:var(--bg-primary);-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;transition:background-color .3s ease,color .3s ease}h1,h2,h3,h4,h5,h6{margin-bottom:.5rem;font-weight:600}h1,h2,h3{color:var(--text-primary)}h1{font-size:2.5rem}h2{font-size:2rem}h3{font-size:1.5rem}a{color:var(--primary-color);text-decoration:none;transition:var(--transition)}a:hover{color:#ff6b35}.btn{display:inline-block;padding:.75rem 1.5rem;border:none;border-radius:var(--border-radius);font-size:1rem;cursor:pointer;transition:var(--transition);font-weight:500;text-align:center;text-decoration:none}.btn:disabled{opacity:.5;cursor:not-allowed}.btn-primary{background-color:#ff6b35;color:#fff}.btn-primary:hover:not(:disabled){background-color:#e55a26;transform:translateY(-2px);box-shadow:var(--box-shadow-md)}.btn-secondary{background-color:#1a4d6f;color:#fff}.btn-secondary:hover:not(:disabled){background-color:#0f3450}.btn-success{background-color:var(--success-color);color:#fff}.btn-success:hover:not(:disabled){background-color:#218838}.btn-danger{background-color:var(--danger-color);color:#fff}.btn-danger:hover:not(:disabled){background-color:#c82333}.btn-lg{padding:1rem 2rem;font-size:1.1rem}.btn-block{width:100%}.form-group{margin-bottom:1.5rem}.form-group label{display:block;margin-bottom:.5rem;font-weight:600}.form-control,input,select,textarea{width:100%;padding:.75rem;border:2px solid var(--border-color);border-radius:var(--border-radius);font-size:1rem;font-family:inherit;transition:var(--transition);background-color:var(--card-bg);color:var(--text-primary)}.form-control:focus,input:focus,select:focus,textarea:focus{outline:none;border-color:var(--accent-color);box-shadow:0 0 0 3px #ff6b351a}.form-control.is-invalid{border-color:var(--danger-color)}.error-text{color:var(--danger-color);font-size:.875rem;margin-top:.25rem;display:block}.alert{padding:1rem;margin-bottom:1rem;border-radius:var(--border-radius);border:1px solid}.alert-danger{background-color:#f8d7da;color:#721c24;border-color:#f5c6cb}.alert-success{background-color:#d4edda;color:#155724;border-color:#c3e6cb}.alert-warning{background-color:#fff3cd;color:#856404;border-color:#ffeeba}.alert-info{background-color:#d1ecf1;color:#0c5460;border-color:#bee5eb}.text-center{text-align:center}p{white-space:pre-line}.text-right{text-align:right}.text-left{text-align:left}.mt-1{margin-top:.5rem}.mt-2{margin-top:1rem}.mt-3{margin-top:1.5rem}.mt-4{margin-top:2rem}.mt-5{margin-top:3rem}.mb-1{margin-bottom:.5rem}.mb-2{margin-bottom:1rem}.mb-3{margin-bottom:1.5rem}.mb-4{margin-bottom:2rem}.mb-5{margin-bottom:3rem}.p-1{padding:.5rem}.p-2{padding:1rem}.p-3{padding:1.5rem}.p-4{padding:2rem}.gap-1{gap:.5rem}.gap-2{gap:1rem}.gap-3{gap:1.5rem}@media(max-width:768px){body{font-size:.95rem}h1{font-size:1.75rem}h2{font-size:1.5rem}.btn-lg{padding:.75rem 1.5rem;font-size:1rem}}