/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #6366f1;
    --primary-dark: #4f46e5;
    --primary-light: #818cf8;
    --secondary-color: #8b5cf6;
    --accent-color: #ec4899;
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-dark: #111827;
    --border-color: #e5e7eb;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

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

/* Header */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
    z-index: 1000;
    transition: all 0.3s ease;
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 0;
    gap: 2rem;
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    text-decoration: none;
    font-weight: 700;
    font-size: 1.5rem;
    color: var(--text-primary);
}

.logo-text {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav {
    display: flex;
    gap: 2rem;
    flex: 1;
    justify-content: center;
}

.nav-link {
    text-decoration: none;
    color: var(--text-secondary);
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary-color);
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: 2px;
}

.search-box {
    position: relative;
    flex: 0 0 300px;
}

.search-input {
    width: 100%;
    padding: 0.75rem 1rem 0.75rem 2.5rem;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    font-size: 0.9rem;
    transition: all 0.3s ease;
    background: var(--bg-secondary);
}

.search-input:focus {
    outline: none;
    border-color: var(--primary-color);
    background: var(--bg-primary);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

.search-icon {
    position: absolute;
    left: 0.75rem;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-secondary);
    pointer-events: none;
}

/* Hero Section */
.hero {
    position: relative;
    min-height: 600px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-top: 80px;
    overflow: hidden;
}

.hero-background {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    z-index: -1;
}

.hero-background::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><defs><pattern id="grid" width="100" height="100" patternUnits="userSpaceOnUse"><path d="M 100 0 L 0 0 0 100" fill="none" stroke="rgba(255,255,255,0.1)" stroke-width="1"/></pattern></defs><rect width="100%" height="100%" fill="url(%23grid)"/></svg>');
    opacity: 0.3;
}

.gradient-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(180deg, rgba(99, 102, 241, 0.8) 0%, rgba(139, 92, 246, 0.6) 100%);
}

.hero-content {
    text-align: center;
    color: white;
    z-index: 1;
    padding: 2rem 0;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
    line-height: 1.2;
    animation: fadeInUp 0.8s ease;
}

.hero-subtitle {
    font-size: 1.25rem;
    margin-bottom: 3rem;
    opacity: 0.9;
    animation: fadeInUp 0.8s ease 0.2s both;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 4rem;
    margin-top: 3rem;
    animation: fadeInUp 0.8s ease 0.4s both;
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 0.9rem;
    opacity: 0.8;
}

/* Categories */
.categories {
    padding: 5rem 0;
    background: var(--bg-secondary);
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 3rem;
    text-align: center;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
    gap: 1.5rem;
}

.category-card {
    background: var(--bg-primary);
    padding: 2rem;
    border-radius: 16px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s ease;
    border: 2px solid transparent;
    box-shadow: var(--shadow-sm);
}

.category-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.category-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.category-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

.category-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Videos Section */
.videos-section {
    padding: 5rem 0;
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 3rem;
    flex-wrap: wrap;
    gap: 1rem;
}

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

.filter-btn {
    padding: 0.5rem 1.25rem;
    border: 2px solid var(--border-color);
    background: var(--bg-primary);
    border-radius: 25px;
    cursor: pointer;
    font-weight: 500;
    transition: all 0.3s ease;
    color: var(--text-secondary);
}

.filter-btn:hover,
.filter-btn.active {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border-color: transparent;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.videos-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 2rem;
}

.video-card {
    background: var(--bg-primary);
    border-radius: 16px;
    overflow: hidden;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: var(--shadow-sm);
    border: 1px solid var(--border-color);
}

.video-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-xl);
}

.video-thumbnail {
    position: relative;
    width: 100%;
    padding-top: 56.25%; /* 16:9 aspect ratio */
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    overflow: hidden;
}

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

.play-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.3);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity 0.3s ease;
}

.video-card:hover .play-overlay {
    opacity: 1;
}

.play-button {
    width: 60px;
    height: 60px;
    background: rgba(255, 255, 255, 0.9);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: transform 0.3s ease;
}

.play-button:hover {
    transform: scale(1.1);
}

.play-button svg {
    width: 24px;
    height: 24px;
    fill: var(--primary-color);
    margin-left: 3px;
}

.video-info {
    padding: 1.25rem;
}

.video-title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.video-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.video-category {
    padding: 0.25rem 0.75rem;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border-radius: 12px;
    font-size: 0.75rem;
    font-weight: 500;
}

/* About Section */
.about {
    padding: 5rem 0;
    background: var(--bg-secondary);
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.about-text {
    font-size: 1.125rem;
    color: var(--text-secondary);
    margin-bottom: 3rem;
    line-height: 1.8;
}

.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.feature {
    padding: 2rem;
    background: var(--bg-primary);
    border-radius: 16px;
    box-shadow: var(--shadow-sm);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.feature h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.feature p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* Footer */
.footer {
    background: var(--bg-dark);
    color: white;
    padding: 3rem 0 1rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

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

.footer-section p,
.footer-section a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    display: block;
    margin-bottom: 0.5rem;
    transition: color 0.3s ease;
}

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

.social-links {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.social-link {
    padding: 0.5rem 1rem;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 8px;
    transition: all 0.3s ease;
}

.social-link:hover {
    background: var(--primary-color);
    color: white;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.5);
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    z-index: 2000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.9);
    backdrop-filter: blur(5px);
    animation: fadeIn 0.3s ease;
}

.modal-content {
    position: relative;
    margin: 2% auto;
    max-width: 90%;
    max-height: 90vh;
    background: var(--bg-primary);
    border-radius: 16px;
    padding: 2rem;
    overflow-y: auto;
    animation: slideUp 0.3s ease;
}

.close-modal {
    position: absolute;
    top: 1rem;
    right: 1rem;
    font-size: 2rem;
    font-weight: bold;
    color: var(--text-secondary);
    cursor: pointer;
    z-index: 10;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    background: var(--bg-secondary);
    transition: all 0.3s ease;
}

.close-modal:hover {
    background: var(--primary-color);
    color: white;
    transform: rotate(90deg);
}

.modal-video-container {
    position: relative;
    width: 100%;
    padding-top: 56.25%;
    margin-bottom: 1.5rem;
    border-radius: 12px;
    overflow: hidden;
}

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

.modal-info h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.modal-info p {
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

/* Animations */
@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideUp {
    from {
        transform: translateY(50px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

/* Responsive Design */
@media (max-width: 768px) {
    .header-content {
        flex-wrap: wrap;
    }

    .nav {
        order: 3;
        width: 100%;
        justify-content: flex-start;
        gap: 1rem;
    }

    .search-box {
        flex: 1;
        min-width: 200px;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-subtitle {
        font-size: 1rem;
    }

    .hero-stats {
        gap: 2rem;
    }

    .stat-number {
        font-size: 2rem;
    }

    .section-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .videos-grid {
        grid-template-columns: 1fr;
    }

    .categories-grid {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    }

    .modal-content {
        max-width: 95%;
        padding: 1rem;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }

    .hero-stats {
        flex-direction: column;
        gap: 1.5rem;
    }

    .filter-buttons {
        width: 100%;
    }

    .filter-btn {
        flex: 1;
        text-align: center;
    }
}