* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
}

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

/* Header */
.header {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.logo {
    width: 40px;
    height: 40px;
}

.brand-text {
    font-size: 1.25rem;
    font-weight: 700;
    color: #2563eb;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s;
}

.nav-link:hover,
.nav-link.active {
    color: #2563eb;
}

.nav-toggle {
    display: none;
    flex-direction: column;
    background: none;
    border: none;
    cursor: pointer;
}

.nav-toggle span {
    width: 25px;
    height: 3px;
    background: #333;
    margin: 3px 0;
    transition: 0.3s;
}

/* Main */
.main {
    min-height: calc(100vh - 200px);
}

/* Hero */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 4rem 2rem;
    text-align: center;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
}

.hero-title {
    font-size: 3rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.hero-subtitle {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    text-align: center;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: #2563eb;
    color: white;
}

.btn-primary:hover {
    background: #1d4ed8;
    transform: translateY(-2px);
}

.btn-secondary {
    background: #f3f4f6;
    color: #333;
}

.btn-secondary:hover {
    background: #e5e7eb;
}

/* Sections */
.section-title {
    font-size: 2rem;
    margin-bottom: 2rem;
    text-align: center;
    color: #333;
}

.featured-section,
.categories-preview {
    padding: 4rem 0;
}

.categories-preview {
    background: #f8fafc;
}

/* Video Grid */
.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.video-card {
    background: white;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    transition: transform 0.3s, box-shadow 0.3s;
}

.video-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 25px rgba(0,0,0,0.15);
}

.video-thumbnail {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.video-content {
    padding: 1.5rem;
}

.video-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: #333;
}

.video-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1rem;
    font-size: 0.875rem;
    color: #666;
}

.video-channel,
.video-category,
.video-duration,
.video-views {
    background: #f3f4f6;
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
}

.video-description {
    color: #666;
    margin-bottom: 1rem;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.video-link {
    color: #2563eb;
    text-decoration: none;
    font-weight: 600;
}

.video-link:hover {
    text-decoration: underline;
}

/* Category Grid */
.category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.category-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
    transition: transform 0.3s;
}

.category-card:hover {
    transform: translateY(-2px);
}

.category-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #333;
}

.category-card p {
    color: #666;
    margin-bottom: 1.5rem;
}

/* Page Header */
.page-header {
    background: #f8fafc;
    padding: 3rem 0;
    text-align: center;
}

.page-header h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: #333;
}

.page-header p {
    font-size: 1.1rem;
    color: #666;
}

/* Directory Controls */
.directory-controls {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    margin-bottom: 2rem;
    padding: 2rem 0;
}

.search-box {
    display: flex;
    flex: 1;
    min-width: 300px;
}

.search-input {
    flex: 1;
    padding: 0.75rem;
    border: 2px solid #e5e7eb;
    border-radius: 8px 0 0 8px;
    font-size: 1rem;
}

.search-btn {
    padding: 0.75rem 1.5rem;
    background: #2563eb;
    color: white;
    border: none;
    border-radius: 0 8px 8px 0;
    cursor: pointer;
}

.filter-controls {
    display: flex;
    gap: 1rem;
}

.filter-select {
    padding: 0.75rem;
    border: 2px solid #e5e7eb;
    border-radius: 8px;
    font-size: 1rem;
    background: white;
}

/* Video Detail */
.video-detail {
    padding: 2rem 0;
}

.video-player-container {
    margin-bottom: 2rem;
}

.video-placeholder {
    background: #f3f4f6;
    padding: 4rem;
    text-align: center;
    border-radius: 12px;
}

.video-embed {
    width: 100%;
    height: 500px;
    border: none;
    border-radius: 12px;
}

.video-info h1 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: #333;
}

.video-info .video-meta {
    margin-bottom: 2rem;
    font-size: 1rem;
}

.video-description,
.video-topics {
    margin-bottom: 2rem;
}

.video-description h3,
.video-topics h3 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
    color: #333;
}

.topic-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.topic-tag {
    background: #2563eb;
    color: white;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.875rem;
}

.content-notice {
    background: #fef3c7;
    border: 1px solid #f59e0b;
    padding: 1rem;
    border-radius: 8px;
    margin-top: 2rem;
}

/* Categories Listing */
.category-section {
    margin-bottom: 4rem;
}

.category-section h2 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: #333;
}

.category-section p {
    color: #666;
    margin-bottom: 2rem;
    font-size: 1.1rem;
}

/* Contact */
.contact-content {
    padding: 2rem 0;
}

.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    margin-bottom: 4rem;
}

.contact-info h2,
.contact-form h2 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #333;
}

.contact-details {
    margin-top: 2rem;
}

.contact-item {
    margin-bottom: 2rem;
}

.contact-item h3 {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
    color: #333;
}

.contact-item p {
    color: #666;
}

.contact-item a {
    color: #2563eb;
    text-decoration: none;
}

.contact-item a:hover {
    text-decoration: underline;
}

/* Forms */
.form {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.form-group {
    display: flex;
    flex-direction: column;
}

.form-group label {
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: #333;
}

.form-input,
.form-select,
.form-textarea {
    padding: 0.75rem;
    border: 2px solid #e5e7eb;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.3s;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    outline: none;
    border-color: #2563eb;
}

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

/* FAQ */
.faq-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.faq-item {
    background: #f8fafc;
    padding: 1.5rem;
    border-radius: 8px;
}

.faq-item h3 {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
    color: #333;
}

.faq-item p {
    color: #666;
}

/* Legal Content */
.legal-content {
    padding: 2rem 0;
}

.legal-section {
    margin-bottom: 3rem;
}

.legal-section h2 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #333;
}

.legal-section h3 {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
    color: #333;
}

.legal-section ul {
    margin: 1rem 0 1rem 2rem;
}

.legal-section li {
    margin-bottom: 0.5rem;
    color: #666;
}

.legal-section a {
    color: #2563eb;
    text-decoration: none;
}

.legal-section a:hover {
    text-decoration: underline;
}

/* Footer */
.footer {
    background: #1f2937;
    color: white;
    padding: 3rem 0 1rem;
    margin-top: 4rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h3,
.footer-section h4 {
    margin-bottom: 1rem;
    color: white;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: #d1d5db;
    text-decoration: none;
    transition: color 0.3s;
}

.footer-section a:hover {
    color: white;
}

.footer-bottom {
    border-top: 1px solid #374151;
    padding-top: 1rem;
    text-align: center;
    color: #9ca3af;
}

/* Responsive */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .hero-title {
        font-size: 2rem;
    }
    
    .hero-subtitle {
        font-size: 1rem;
    }
    
    .video-grid {
        grid-template-columns: 1fr;
    }
    
    .contact-grid {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .directory-controls {
        flex-direction: column;
    }
    
    .search-box {
        min-width: 100%;
    }
    
    .filter-controls {
        flex-wrap: wrap;
    }
    
    .filter-select {
        flex: 1;
        min-width: 150px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .nav {
        padding: 1rem 15px;
    }
    
    .hero {
        padding: 2rem 1rem;
    }
    
    .video-embed {
        height: 250px;
    }
    
    .category-grid {
        grid-template-columns: 1fr;
    }
}