* {
    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: 100;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: bold;
    color: #e74c3c;
}

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

.nav {
    display: flex;
    gap: 2rem;
}

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

.nav-link:hover,
.nav-link.active {
    color: #e74c3c;
}

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

.hero-content h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 24px;
    text-decoration: none;
    border-radius: 6px;
    font-weight: 600;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
    font-size: 1rem;
}

.btn-primary {
    background: #e74c3c;
    color: white;
}

.btn-primary:hover {
    background: #c0392b;
    transform: translateY(-2px);
}

.btn-outline {
    background: transparent;
    color: #e74c3c;
    border: 2px solid #e74c3c;
}

.btn-outline:hover {
    background: #e74c3c;
    color: white;
}

/* Video Grid */
.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.video-card {
    background: white;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    transition: transform 0.3s, box-shadow 0.3s;
}

.video-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 30px rgba(0,0,0,0.15);
}

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

.video-info {
    padding: 1.5rem;
}

.video-title {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: #333;
}

.video-creator {
    color: #666;
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

.video-meta {
    display: flex;
    justify-content: space-between;
    font-size: 0.8rem;
    color: #888;
    margin-bottom: 1rem;
}

.video-description {
    color: #666;
    font-size: 0.9rem;
    line-height: 1.5;
    margin-bottom: 1rem;
}

.video-topics {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.topic-tag {
    background: #f8f9fa;
    color: #495057;
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    font-size: 0.75rem;
}

.category-badge {
    display: inline-block;
    background: #e74c3c;
    color: white;
    padding: 0.25rem 0.5rem;
    border-radius: 4px;
    font-size: 0.75rem;
    text-transform: uppercase;
    font-weight: 600;
}

/* Sections */
.featured,
.categories-preview,
.videos-page,
.categories-page,
.page-content {
    padding: 4rem 0;
}

.page-header {
    text-align: center;
    margin-bottom: 3rem;
}

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

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

/* Categories */
.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.categories-grid.large {
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.category-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    text-align: center;
    transition: transform 0.3s;
}

.category-card:hover {
    transform: translateY(-3px);
}

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

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

.category-stats {
    font-size: 0.9rem;
    color: #888;
    margin-bottom: 1rem;
}

/* Filters */
.filters {
    background: #f8f9fa;
    padding: 2rem;
    border-radius: 12px;
    margin-bottom: 2rem;
}

.search-box {
    margin-bottom: 1rem;
}

.search-box input {
    width: 100%;
    padding: 12px;
    border: 1px solid #ddd;
    border-radius: 6px;
    font-size: 1rem;
}

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

.filter-controls select {
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 6px;
    font-size: 0.9rem;
    background: white;
}

.results-info {
    margin-bottom: 1rem;
    color: #666;
}

.no-results {
    text-align: center;
    padding: 3rem;
    color: #666;
}

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

.back-link {
    margin-bottom: 2rem;
}

.back-link a {
    color: #e74c3c;
    text-decoration: none;
    font-weight: 500;
}

.video-content {
    margin-bottom: 2rem;
}

.video-player {
    width: 100%;
    max-width: 800px;
    margin: 0 auto 2rem;
}

.video-player iframe {
    width: 100%;
    height: 450px;
    border: none;
    border-radius: 12px;
}

.video-details {
    max-width: 800px;
    margin: 0 auto;
}

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

.video-details .video-meta {
    font-size: 1rem;
    margin-bottom: 2rem;
    justify-content: flex-start;
    gap: 2rem;
}

.video-details .video-description {
    font-size: 1rem;
    line-height: 1.6;
    margin-bottom: 2rem;
}

.disclaimer-box {
    background: #fff3cd;
    border: 1px solid #ffeaa7;
    border-radius: 6px;
    padding: 1rem;
    margin: 2rem 0;
}

.disclaimer-box.important {
    background: #f8d7da;
    border-color: #f5c6cb;
}

.related-videos h3 {
    margin-bottom: 2rem;
    font-size: 1.5rem;
}

/* Contact */
.contact-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: 3rem;
    margin-bottom: 3rem;
}

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

.contact-info h3 {
    color: #e74c3c;
    margin-bottom: 0.5rem;
}

.contact-form {
    background: #f8f9fa;
    padding: 2rem;
    border-radius: 12px;
}

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

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: #333;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px;
    border: 1px solid #ddd;
    border-radius: 6px;
    font-size: 1rem;
}

.form-group textarea {
    resize: vertical;
}

.faq-section {
    margin-top: 3rem;
}

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

.faq-item h3 {
    color: #e74c3c;
    margin-bottom: 0.5rem;
}

/* Text Content */
.text-content {
    max-width: 800px;
    margin: 0 auto;
    line-height: 1.8;
}

.text-content h2 {
    color: #333;
    margin: 2rem 0 1rem;
    font-size: 1.5rem;
}

.text-content h3 {
    color: #555;
    margin: 1.5rem 0 0.5rem;
}

.text-content ul,
.text-content ol {
    margin-left: 2rem;
    margin-bottom: 1rem;
}

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

.text-content a {
    color: #e74c3c;
    text-decoration: none;
}

.text-content a:hover {
    text-decoration: underline;
}

/* Footer */
.footer {
    background: #2c3e50;
    color: white;
    padding: 3rem 0 1rem;
}

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

.footer-section h4 {
    margin-bottom: 1rem;
    color: #e74c3c;
}

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

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

.footer-section ul li a {
    color: #bdc3c7;
    text-decoration: none;
    transition: color 0.3s;
}

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

.footer-bottom {
    border-top: 1px solid #34495e;
    padding-top: 1rem;
    text-align: center;
    color: #bdc3c7;
}

/* Utilities */
.text-center {
    text-align: center;
}

.mt-2 { margin-top: 2rem; }
.mb-2 { margin-bottom: 2rem; }

/* Responsive */
@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        gap: 1rem;
    }
    
    .nav {
        gap: 1rem;
    }
    
    .hero-content h1 {
        font-size: 2rem;
    }
    
    .video-grid {
        grid-template-columns: 1fr;
    }
    
    .categories-grid {
        grid-template-columns: 1fr;
    }
    
    .contact-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .filter-controls {
        flex-direction: column;
    }
    
    .filter-controls select {
        width: 100%;
    }
    
    .video-player iframe {
        height: 250px;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero {
        padding: 2rem 0;
    }
    
    .hero-content h1 {
        font-size: 1.75rem;
    }
    
    .featured,
    .categories-preview,
    .videos-page,
    .categories-page,
    .page-content {
        padding: 2rem 0;
    }
    
    .video-info {
        padding: 1rem;
    }
    
    .category-card {
        padding: 1.5rem;
    }
}