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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 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;
}

.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-name {
    font-size: 1.5rem;
    font-weight: 700;
    color: hsl(175, 70%, 50%);
}

.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: hsl(175, 70%, 50%);
}

/* Hero Section */
.hero {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
    padding: 4rem 2rem;
    max-width: 1200px;
    margin: 0 auto;
}

.hero-content h1 {
    font-size: 3rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: #2c3e50;
}

.hero-content p {
    font-size: 1.2rem;
    color: #666;
    margin-bottom: 2rem;
}

.cta-button {
    display: inline-block;
    background: hsl(175, 70%, 50%);
    color: white;
    padding: 1rem 2rem;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    transition: background 0.3s;
}

.cta-button:hover {
    background: hsl(175, 70%, 40%);
}

.hero-image img {
    width: 100%;
    height: auto;
}

/* 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: 12px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.1);
    overflow: hidden;
    transition: transform 0.3s, box-shadow 0.3s;
    text-decoration: none;
    color: inherit;
}

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

.video-thumbnail {
    position: relative;
    width: 100%;
    height: 200px;
    overflow: hidden;
}

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

.video-duration {
    position: absolute;
    bottom: 8px;
    right: 8px;
    background: rgba(0,0,0,0.8);
    color: white;
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 0.8rem;
}

.video-info {
    padding: 1.5rem;
}

.video-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    line-height: 1.4;
}

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

.video-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.8rem;
    color: #888;
}

.video-category {
    background: hsl(175, 70%, 90%);
    color: hsl(175, 70%, 30%);
    padding: 2px 8px;
    border-radius: 12px;
    font-size: 0.7rem;
}

/* Category Grid */
.category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-top: 2rem;
}

.category-card {
    background: linear-gradient(135deg, hsl(175, 70%, 50%), hsl(175, 70%, 60%));
    color: white;
    padding: 2rem;
    border-radius: 12px;
    text-decoration: none;
    transition: transform 0.3s;
}

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

.category-card h3 {
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
}

.category-card p {
    opacity: 0.9;
}

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

.categories-preview {
    background: #f8f9fa;
}

section h2 {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 1rem;
    color: #2c3e50;
}

/* Search & Filter */
.search-filter {
    background: #f8f9fa;
    padding: 2rem;
    border-radius: 12px;
    margin-bottom: 3rem;
}

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

.search-input {
    flex: 1;
    padding: 0.8rem;
    border: 2px solid #ddd;
    border-radius: 8px;
    font-size: 1rem;
}

.search-input:focus {
    outline: none;
    border-color: hsl(175, 70%, 50%);
}

.filter-tabs {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
}

.filter-tab {
    padding: 0.5rem 1rem;
    background: #fff;
    border: 2px solid #ddd;
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.3s;
}

.filter-tab:hover,
.filter-tab.active {
    background: hsl(175, 70%, 50%);
    color: white;
    border-color: hsl(175, 70%, 50%);
}

/* Video Detail */
.video-detail {
    max-width: 1000px;
    margin: 0 auto;
    padding: 2rem;
}

.video-player {
    width: 100%;
    height: 500px;
    background: #000;
    border-radius: 12px;
    margin-bottom: 2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.2rem;
}

.video-details h1 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: #2c3e50;
}

.video-details-meta {
    display: flex;
    gap: 2rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.video-details-meta span {
    color: #666;
}

.video-description {
    line-height: 1.8;
    color: #555;
}

.video-topics {
    margin-top: 2rem;
}

.topics-list {
    display: flex;
    gap: 0.5rem;
    flex-wrap: wrap;
    margin-top: 0.5rem;
}

.topic-tag {
    background: hsl(175, 70%, 90%);
    color: hsl(175, 70%, 30%);
    padding: 4px 12px;
    border-radius: 16px;
    font-size: 0.8rem;
}

/* Footer */
.footer {
    background: #2c3e50;
    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: hsl(175, 70%, 70%);
}

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

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

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

.footer-section a:hover {
    color: hsl(175, 70%, 70%);
}

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

/* Responsive */
@media (max-width: 768px) {
    .nav {
        flex-direction: column;
        gap: 1rem;
    }
    
    .nav-menu {
        gap: 1rem;
    }
    
    .hero {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-content h1 {
        font-size: 2rem;
    }
    
    .video-grid {
        grid-template-columns: 1fr;
    }
    
    .category-grid {
        grid-template-columns: 1fr;
    }
    
    .search-box {
        flex-direction: column;
    }
    
    .video-details-meta {
        flex-direction: column;
        gap: 0.5rem;
    }
}

/* Content Pages */
.content-page {
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem;
}

.content-page h1 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: #2c3e50;
}

.content-page h2 {
    font-size: 1.8rem;
    margin: 2rem 0 1rem;
    color: #34495e;
}

.content-page p {
    margin-bottom: 1rem;
    line-height: 1.8;
}

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

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

.contact-info {
    background: #f8f9fa;
    padding: 2rem;
    border-radius: 12px;
    margin: 2rem 0;
}

.contact-info h3 {
    margin-bottom: 1rem;
    color: hsl(175, 70%, 40%);
}

.contact-info p {
    margin-bottom: 0.5rem;
}

.contact-info a {
    color: hsl(175, 70%, 50%);
    text-decoration: none;
}

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