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

:root {
    --primary-color: #1a73e8;
    --secondary-color: #4285f4;
    --accent-color: #0d47a1;
    --dark-color: #0a1929;
    --light-color: #f5f9ff;
    --text-color: #1e293b;
    --gray-color: #64748b;
    --border-color: #e2e8f0;
    --shadow: 0 4px 20px rgba(26, 115, 232, 0.1);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'Noto Sans', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background: linear-gradient(135deg, #f5f9ff 0%, #e8f2ff 100%);
    overflow-x: hidden;
    position: relative;
}

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

#particles-bg {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 0;
    overflow: hidden;
}

.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    box-shadow: 0 2px 20px rgba(26, 115, 232, 0.08);
    z-index: 1000;
    transition: var(--transition);
}

.header.scrolled {
    box-shadow: 0 4px 30px rgba(26, 115, 232, 0.12);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
    cursor: pointer;
    transition: var(--transition);
}

.logo:hover {
    opacity: 0.9;
    transform: translateX(2px);
}

.logo-icon {
    color: var(--primary-color);
    animation: pulse 2s ease-in-out infinite;
}

.logo-text {
    color: var(--dark-color);
}

.logo-highlight {
    color: var(--primary-color);
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.05); }
}

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

.nav-link {
    display: flex;
    align-items: center;
    gap: 0.4rem;
    padding: 0.6rem 1rem;
    color: var(--gray-color);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    border-radius: 8px;
    transition: var(--transition);
    position: relative;
}

.nav-link svg {
    width: 18px;
    height: 18px;
}

.nav-link:hover {
    color: var(--primary-color);
    background: var(--light-color);
}

.nav-link.active {
    color: var(--primary-color);
    background: linear-gradient(135deg, #e8f2ff 0%, #dae8ff 100%);
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -8px;
    left: 50%;
    transform: translateX(-50%);
    width: 24px;
    height: 3px;
    background: var(--primary-color);
    border-radius: 2px;
}

.search-box {
    display: flex;
    align-items: center;
    gap: 0;
    background: var(--light-color);
    border: 2px solid var(--border-color);
    border-radius: 24px;
    padding: 0.4rem 0.8rem;
    transition: var(--transition);
}

.search-box:focus-within {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(26, 115, 232, 0.1);
}

.search-input {
    border: none;
    outline: none;
    background: transparent;
    padding: 0.2rem 0.5rem;
    font-size: 0.9rem;
    color: var(--text-color);
    width: 200px;
}

.search-input::placeholder {
    color: var(--gray-color);
}

.search-btn {
    background: none;
    border: none;
    cursor: pointer;
    color: var(--gray-color);
    padding: 0.2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
}

.search-btn:hover {
    color: var(--primary-color);
}

main {
    padding-top: 80px;
    position: relative;
    z-index: 1;
}

.hero-section {
    min-height: 600px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #0d47a1 0%, #1a73e8 50%, #4285f4 100%);
    padding: 4rem 0;
    position: relative;
    overflow: hidden;
}

.hero-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 1200 600"><rect fill="%231a73e8" width="1200" height="600"/><g fill-opacity="0.05"><circle fill="%23fff" cx="400" cy="200" r="200"/><circle fill="%23fff" cx="800" cy="400" r="150"/></g></svg>');
    opacity: 0.3;
    animation: float 20s ease-in-out infinite;
}

.hero-content-wrapper {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    position: relative;
    z-index: 1;
}

.hero-text {
    text-align: center;
    color: white;
    max-width: 800px;
    margin: 0 auto 3rem;
}

.hero-title {
    font-size: 3rem;
    font-weight: 800;
    margin-bottom: 1rem;
    line-height: 1.2;
    text-shadow: 0 2px 10px rgba(0, 0, 0, 0.2);
}

.hero-desc {
    font-size: 1.25rem;
    margin-bottom: 0.8rem;
    opacity: 0.95;
}

.hero-highlight {
    font-size: 1.1rem;
    opacity: 0.9;
    margin-bottom: 2rem;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
}

.hero-btn {
    display: inline-block;
    padding: 1rem 2.5rem;
    font-size: 1.1rem;
    font-weight: 600;
    text-decoration: none;
    border-radius: 30px;
    transition: var(--transition);
}

.hero-btn.primary {
    background: white;
    color: var(--primary-color);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
}

.hero-btn.primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.3);
}

.hero-btn.secondary {
    background: rgba(255, 255, 255, 0.2);
    color: white;
    border: 2px solid white;
}

.hero-btn.secondary:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-3px);
}

.hero-stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    max-width: 900px;
    margin: 0 auto;
}

.stat-card {
    background: rgba(255, 255, 255, 0.15);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 16px;
    padding: 2rem;
    text-align: center;
    color: white;
    transition: var(--transition);
}

.stat-card:hover {
    background: rgba(255, 255, 255, 0.25);
    transform: translateY(-5px);
}

.stat-icon {
    margin-bottom: 1rem;
    opacity: 0.9;
}

.stat-number {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 1rem;
    opacity: 0.9;
}

.section {
    padding: 5rem 0;
}

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

.section-title {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--dark-color);
    margin-bottom: 0.8rem;
}

.section-title svg {
    color: var(--primary-color);
}

.section-subtitle {
    font-size: 1.1rem;
    color: var(--gray-color);
}

.hot-section {
    background: white;
}

.hot-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
}

.hot-card {
    background: white;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    position: relative;
}

.hot-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 8px 30px rgba(26, 115, 232, 0.15);
}

.hot-card.featured {
    grid-column: span 2;
}

.hot-badge, .hot-rank {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: linear-gradient(135deg, #ff4757 0%, #ff6348 100%);
    color: white;
    padding: 0.4rem 1rem;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 600;
    z-index: 2;
}

.hot-rank {
    background: var(--primary-color);
}

.hot-thumbnail {
    position: relative;
    aspect-ratio: 16/9;
    background: linear-gradient(135deg, #e8f2ff 0%, #dae8ff 100%);
    overflow: hidden;
}

.thumbnail-placeholder {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 100%;
    color: var(--primary-color);
    opacity: 0.3;
}

.video-duration, .video-quality {
    position: absolute;
    bottom: 0.8rem;
    background: rgba(0, 0, 0, 0.8);
    color: white;
    padding: 0.3rem 0.8rem;
    border-radius: 6px;
    font-size: 0.85rem;
    font-weight: 500;
}

.video-duration {
    left: 0.8rem;
}

.video-quality {
    right: 0.8rem;
    background: linear-gradient(135deg, #1a73e8 0%, #4285f4 100%);
}

.hot-info {
    padding: 1.5rem;
}

.hot-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--dark-color);
    margin-bottom: 0.8rem;
    line-height: 1.4;
}

.hot-desc {
    font-size: 0.95rem;
    color: var(--gray-color);
    margin-bottom: 1rem;
    line-height: 1.5;
}

.hot-meta, .video-meta, .ranking-meta, .latest-meta {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
    font-size: 0.9rem;
    color: var(--gray-color);
}

.meta-tag {
    background: var(--light-color);
    color: var(--primary-color);
    padding: 0.3rem 0.8rem;
    border-radius: 12px;
    font-size: 0.85rem;
    font-weight: 500;
}

.meta-item {
    display: flex;
    align-items: center;
    gap: 0.3rem;
}

.meta-item svg {
    width: 14px;
    height: 14px;
}

.categories-section {
    background: var(--light-color);
}

.categories-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
    gap: 2rem;
}

.category-card {
    background: white;
    border-radius: 16px;
    padding: 2rem;
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.category-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    transform: scaleX(0);
    transition: var(--transition);
}

.category-card:hover::before {
    transform: scaleX(1);
}

.category-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 8px 30px rgba(26, 115, 232, 0.15);
}

.category-icon {
    margin-bottom: 1.5rem;
    color: var(--primary-color);
}

.category-title {
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--dark-color);
    margin-bottom: 0.8rem;
}

.category-desc {
    font-size: 0.95rem;
    color: var(--gray-color);
    margin-bottom: 1rem;
}

.category-count {
    font-size: 0.9rem;
    color: var(--primary-color);
    font-weight: 600;
    margin-bottom: 1rem;
}

.category-link {
    display: inline-block;
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    font-size: 0.95rem;
    padding: 0.6rem 1.5rem;
    border: 2px solid var(--primary-color);
    border-radius: 24px;
    transition: var(--transition);
}

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

.ranking-section {
    background: white;
}

.ranking-tabs {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.ranking-tab {
    background: var(--light-color);
    border: none;
    padding: 0.8rem 2rem;
    border-radius: 24px;
    font-size: 1rem;
    font-weight: 600;
    color: var(--gray-color);
    cursor: pointer;
    transition: var(--transition);
}

.ranking-tab.active,
.ranking-tab:hover {
    background: var(--primary-color);
    color: white;
}

.ranking-list {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.ranking-item {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    background: white;
    border: 2px solid var(--border-color);
    border-radius: 16px;
    padding: 1.5rem;
    transition: var(--transition);
}

.ranking-item:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow);
}

.ranking-number {
    font-size: 2rem;
    font-weight: 800;
    color: var(--gray-color);
    min-width: 50px;
    text-align: center;
}

.ranking-number.top-1 {
    color: #ffd700;
}

.ranking-number.top-2 {
    color: #c0c0c0;
}

.ranking-number.top-3 {
    color: #cd7f32;
}

.ranking-thumbnail {
    width: 120px;
    height: 80px;
    border-radius: 8px;
    overflow: hidden;
    flex-shrink: 0;
}

.ranking-thumbnail .thumbnail-placeholder {
    width: 100%;
    height: 100%;
    background: var(--light-color);
}

.ranking-info {
    flex: 1;
}

.ranking-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--dark-color);
    margin-bottom: 0.8rem;
}

.ranking-score {
    background: linear-gradient(135deg, #ffd700 0%, #ffed4e 100%);
    color: var(--dark-color);
    padding: 0.3rem 0.8rem;
    border-radius: 12px;
    font-size: 0.9rem;
    font-weight: 600;
}

.ranking-trend {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: var(--light-color);
}

.ranking-trend.up {
    color: #10b981;
    background: #d1fae5;
}

.ranking-trend.down {
    color: #ef4444;
    background: #fee2e2;
}

.ranking-trend.same {
    color: var(--gray-color);
    background: var(--light-color);
}

.recommended-section {
    background: var(--light-color);
}

.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
}

.video-card {
    background: white;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.video-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 8px 30px rgba(26, 115, 232, 0.15);
}

.video-thumbnail {
    position: relative;
    aspect-ratio: 16/9;
    background: linear-gradient(135deg, #e8f2ff 0%, #dae8ff 100%);
    overflow: hidden;
}

.video-tag {
    position: absolute;
    top: 0.8rem;
    left: 0.8rem;
    background: linear-gradient(135deg, #1a73e8 0%, #4285f4 100%);
    color: white;
    padding: 0.3rem 0.8rem;
    border-radius: 12px;
    font-size: 0.85rem;
    font-weight: 600;
}

.video-info {
    padding: 1.5rem;
}

.video-title {
    font-size: 1rem;
    font-weight: 600;
    color: var(--dark-color);
    margin-bottom: 0.8rem;
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.latest-section {
    background: white;
}

.latest-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.latest-card {
    background: white;
    border: 2px solid var(--border-color);
    border-radius: 16px;
    overflow: hidden;
    transition: var(--transition);
    position: relative;
}

.latest-card:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow);
}

.latest-badge {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: linear-gradient(135deg, #ff4757 0%, #ff6348 100%);
    color: white;
    padding: 0.3rem 0.8rem;
    border-radius: 12px;
    font-size: 0.85rem;
    font-weight: 600;
    z-index: 2;
}

.latest-thumbnail {
    position: relative;
    aspect-ratio: 16/9;
    background: linear-gradient(135deg, #e8f2ff 0%, #dae8ff 100%);
    overflow: hidden;
}

.latest-info {
    padding: 1.5rem;
}

.latest-title {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--dark-color);
    margin-bottom: 0.8rem;
    line-height: 1.4;
}

.latest-desc {
    font-size: 0.9rem;
    color: var(--gray-color);
    margin-bottom: 1rem;
    line-height: 1.5;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.about-section {
    background: var(--light-color);
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
}

.about-heading {
    font-size: 2rem;
    font-weight: 700;
    color: var(--dark-color);
    margin-bottom: 1.5rem;
}

.about-paragraph {
    font-size: 1.05rem;
    color: var(--gray-color);
    line-height: 1.8;
    margin-bottom: 1.5rem;
}

.about-features {
    display: grid;
    gap: 1.5rem;
    margin-top: 2rem;
}

.feature-item {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    background: white;
    padding: 1.5rem;
    border-radius: 12px;
    box-shadow: var(--shadow);
}

.feature-icon {
    color: var(--primary-color);
    flex-shrink: 0;
}

.feature-text h4 {
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--dark-color);
    margin-bottom: 0.4rem;
}

.feature-text p {
    font-size: 0.95rem;
    color: var(--gray-color);
}

.about-cta {
    display: flex;
    gap: 1rem;
    margin-top: 2rem;
}

.cta-button {
    display: inline-block;
    padding: 0.9rem 2rem;
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    border-radius: 24px;
    transition: var(--transition);
}

.cta-button.primary {
    background: var(--primary-color);
    color: white;
}

.cta-button.primary:hover {
    background: var(--accent-color);
    transform: translateY(-3px);
}

.cta-button.secondary {
    background: white;
    color: var(--primary-color);
    border: 2px solid var(--primary-color);
}

.cta-button.secondary:hover {
    background: var(--primary-color);
    color: white;
}

.about-image {
    display: flex;
    align-items: center;
    justify-content: center;
}

.image-placeholder {
    width: 100%;
    max-width: 400px;
    aspect-ratio: 1;
    background: linear-gradient(135deg, #e8f2ff 0%, #dae8ff 100%);
    border-radius: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary-color);
}

.footer {
    background: linear-gradient(135deg, #0a1929 0%, #0d47a1 100%);
    color: white;
    padding: 4rem 0 2rem;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr repeat(3, 1fr);
    gap: 3rem;
    margin-bottom: 3rem;
}

.footer-title {
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: 1rem;
    color: white;
}

.footer-desc {
    font-size: 1rem;
    opacity: 0.9;
    margin-bottom: 1.5rem;
}

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

.social-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    color: white;
    transition: var(--transition);
}

.social-link:hover {
    background: var(--primary-color);
    transform: translateY(-3px);
}

.footer-heading {
    font-size: 1.2rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    color: white;
}

.footer-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.footer-links a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    transition: var(--transition);
}

.footer-links a:hover {
    color: white;
    padding-left: 0.5rem;
}

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

.footer-bottom p {
    opacity: 0.8;
    font-size: 0.95rem;
    margin: 0.5rem 0;
}

.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 50px;
    height: 50px;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 15px rgba(26, 115, 232, 0.3);
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    z-index: 999;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    background: var(--accent-color);
    transform: translateY(-5px);
}

@media (max-width: 1024px) {
    .hero-title {
        font-size: 2.5rem;
    }

    .hot-card.featured {
        grid-column: span 1;
    }

    .latest-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .about-content {
        grid-template-columns: 1fr;
    }

    .footer-content {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav {
        display: none;
    }

    .hero-title {
        font-size: 2rem;
    }

    .hero-desc {
        font-size: 1.1rem;
    }

    .hero-stats {
        grid-template-columns: 1fr;
    }

    .section-title {
        font-size: 2rem;
    }

    .categories-grid,
    .hot-grid,
    .video-grid {
        grid-template-columns: 1fr;
    }

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

    .footer-content {
        grid-template-columns: 1fr;
    }

    .ranking-item {
        flex-direction: column;
        align-items: flex-start;
    }
}