* {
    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;
    border-bottom: 1px solid #e0e0e0;
    position: sticky;
    top: 0;
    z-index: 100;
}

.header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 20px;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
}

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

.brand-name {
    font-size: 1.5rem;
    font-weight: 600;
    color: #d32f2f;
}

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

.nav-link {
    text-decoration: none;
    color: #666;
    font-weight: 500;
    transition: color 0.3s;
}

.nav-link:hover,
.nav-link.active {
    color: #d32f2f;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #f5f5f5 0%, #e8e8e8 100%);
    padding: 4rem 0;
    text-align: center;
}

.hero-content h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    color: #333;
}

.hero-content p {
    font-size: 1.2rem;
    color: #666;
    margin-bottom: 2rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.cta-button {
    display: inline-block;
    background: #d32f2f;
    color: white;
    padding: 12px 30px;
    text-decoration: none;
    border-radius: 5px;
    font-weight: 600;
    transition: background 0.3s;
}

.cta-button:hover {
    background: #b71c1c;
}

/* Page Header */
.page-header {
    background: #f8f9fa;
    padding: 3rem 0;
    text-align: center;
}

.page-header h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    color: #333;
}

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

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

.video-card {
    background: #fff;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    transition: transform 0.3s, box-shadow 0.3s;
}

.video-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 4px 20px rgba(0,0,0,0.15);
}

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

.video-info {
    padding: 1.5rem;
}

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

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

.video-meta {
    display: flex;
    gap: 1rem;
    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: #f0f0f0;
    padding: 0.25rem 0.5rem;
    border-radius: 12px;
    font-size: 0.8rem;
    color: #666;
}

.watch-btn {
    background: #d32f2f;
    color: white;
    padding: 8px 16px;
    text-decoration: none;
    border-radius: 4px;
    font-size: 0.9rem;
    transition: background 0.3s;
}

.watch-btn:hover {
    background: #b71c1c;
}

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

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

.category-card {
    background: #fff;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 10px 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-card a {
    color: #d32f2f;
    text-decoration: none;
    font-weight: 600;
}

/* Filters */
.video-filters {
    background: #f8f9fa;
    padding: 2rem 0;
}

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

.search-box input,
.filter-select select {
    padding: 10px 15px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 1rem;
}

.search-box input {
    width: 300px;
}

.filter-select select {
    width: 200px;
}

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

.video-detail .container {
    max-width: 1000px;
}

.video-player {
    position: relative;
    padding-bottom: 56.25%;
    height: 0;
    overflow: hidden;
    margin-bottom: 2rem;
    border-radius: 8px;
}

.video-player iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: none;
}

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

.video-header .video-meta {
    margin-bottom: 2rem;
}

.video-content {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
    margin-top: 2rem;
}

.video-main h2 {
    margin-bottom: 1rem;
    color: #333;
}

.video-sidebar {
    background: #f8f9fa;
    padding: 2rem;
    border-radius: 8px;
    height: fit-content;
}

.content-notice {
    background: #e3f2fd;
    padding: 1rem;
    border-radius: 5px;
    border-left: 4px solid #2196f3;
    margin-bottom: 2rem;
}

/* Sections */
.featured-section,
.categories-preview,
.videos-section,
.categories-section,
.content-section,
.contact-section {
    padding: 3rem 0;
}

.featured-section h2,
.categories-preview h2,
.videos-section h2,
.categories-section h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: #333;
}

/* Content Layout */
.content-grid {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 3rem;
    margin-top: 2rem;
}

.content-main h2 {
    margin-top: 2rem;
    margin-bottom: 1rem;
    color: #333;
}

.content-main h2:first-child {
    margin-top: 0;
}

.content-main ul {
    margin-left: 2rem;
    margin-bottom: 1rem;
}

.content-sidebar {
    background: #f8f9fa;
    padding: 2rem;
    border-radius: 8px;
    height: fit-content;
}

.info-box {
    background: #fff;
    padding: 1.5rem;
    border-radius: 8px;
    margin-bottom: 1.5rem;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

.info-box h3 {
    margin-bottom: 1rem;
    color: #333;
}

/* Contact */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    margin-top: 2rem;
}

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

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

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

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

.contact-item a {
    color: #d32f2f;
    text-decoration: none;
}

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

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

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 10px 15px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 1rem;
    font-family: inherit;
}

.form-group textarea {
    resize: vertical;
}

.submit-btn {
    background: #d32f2f;
    color: white;
    padding: 12px 30px;
    border: none;
    border-radius: 5px;
    font-size: 1rem;
    cursor: pointer;
    transition: background 0.3s;
}

.submit-btn:hover {
    background: #b71c1c;
}

/* Legal Content */
.legal-content {
    max-width: 800px;
    margin: 2rem auto;
    line-height: 1.8;
}

.legal-content h2 {
    margin-top: 2rem;
    margin-bottom: 1rem;
    color: #333;
}

.legal-content h2:first-child {
    margin-top: 0;
}

.legal-content ul {
    margin-left: 2rem;
    margin-bottom: 1rem;
}

/* Footer */
.footer {
    background: #333;
    color: #fff;
    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 h4 {
    margin-bottom: 1rem;
    color: #fff;
}

.footer-section a {
    display: block;
    color: #ccc;
    text-decoration: none;
    margin-bottom: 0.5rem;
    transition: color 0.3s;
}

.footer-section a:hover {
    color: #fff;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #555;
    color: #ccc;
}

/* Responsive Design */
@media (max-width: 768px) {
    .header .container {
        flex-direction: column;
        gap: 1rem;
    }
    
    .nav-menu {
        gap: 1rem;
    }
    
    .hero-content h1 {
        font-size: 2rem;
    }
    
    .video-grid {
        grid-template-columns: 1fr;
    }
    
    .content-grid,
    .contact-grid,
    .video-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .filter-controls {
        flex-direction: column;
        align-items: stretch;
    }
    
    .search-box input {
        width: 100%;
    }
    
    .filter-select select {
        width: 100%;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero {
        padding: 2rem 0;
    }
    
    .page-header {
        padding: 2rem 0;
    }
    
    .featured-section,
    .categories-preview,
    .videos-section,
    .categories-section,
    .content-section,
    .contact-section {
        padding: 2rem 0;
    }
}