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

body {
    font-family: 'Microsoft YaHei', 'PingFang SC', 'Hiragino Sans GB', sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
}

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

header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
}

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

.logo {
    font-size: 2rem;
    font-weight: bold;
    background: linear-gradient(45deg, #667eea, #764ba2);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 2rem;
}

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

.nav-links a:hover {
    color: #667eea;
}

.hero {
    padding: 120px 0 80px;
    text-align: center;
    color: white;
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 1rem;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
    animation: fadeInUp 1s ease-out;
}

.hero .subtitle {
    font-size: 1.5rem;
    margin-bottom: 2rem;
    opacity: 0.9;
    animation: fadeInUp 1s ease-out 0.2s both;
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    animation: fadeInUp 1s ease-out 0.4s both;
}

.btn {
    display: inline-block;
    padding: 15px 40px;
    background: linear-gradient(45deg, #ff6b6b, #ee5a24);
    color: white;
    text-decoration: none;
    border-radius: 50px;
    font-weight: 600;
    font-size: 1.1rem;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
    box-shadow: 0 4px 15px rgba(255, 107, 107, 0.4);
}

.btn:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 25px rgba(255, 107, 107, 0.6);
}

.btn-secondary {
    background: linear-gradient(45deg, #667eea, #764ba2);
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.btn-secondary:hover {
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.6);
}

.features {
    background: white;
    padding: 80px 0;
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    background: linear-gradient(45deg, #667eea, #764ba2);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 3rem;
    margin-top: 4rem;
}

.feature-card {
    background: white;
    padding: 3rem 2rem;
    border-radius: 20px;
    text-align: center;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    transition: all 0.3s;
    border: 2px solid transparent;
}

.feature-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
    border-color: #667eea;
}

.feature-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(45deg, #667eea, #764ba2);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 2rem;
    margin: 0 auto 2rem;
}

.feature-title {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1rem;
    color: #333;
}

.feature-desc {
    color: #666;
    line-height: 1.6;
}

.download-section {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 80px 0;
    color: white;
    text-align: center;
}

.download-cards {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.download-card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    padding: 3rem 2rem;
    border-radius: 20px;
    border: 1px solid rgba(255, 255, 255, 0.2);
    transition: all 0.3s;
}

.download-card:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-5px);
}

.version-badge {
    display: inline-block;
    background: linear-gradient(45deg, #ff6b6b, #ee5a24);
    padding: 8px 20px;
    border-radius: 25px;
    font-size: 0.9rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.download-title {
    font-size: 1.8rem;
    font-weight: 600;
    margin-bottom: 1rem;
}

.download-features {
    list-style: none;
    margin: 2rem 0;
    text-align: left;
}

.download-features li {
    padding: 0.5rem 0;
    position: relative;
    padding-left: 2rem;
}

.download-features li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: #4ecdc4;
    font-weight: bold;
}

.video-gallery {
    background: #f8f9fa;
    padding: 80px 0;
}

.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 2rem;
    margin-top: 3rem;
}

.video-card {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
    transition: all 0.3s;
}

.video-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.15);
}

.video-thumbnail {
    width: 100%;
    height: 200px;
    background: linear-gradient(45deg, #667eea, #764ba2);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 3rem;
    position: relative;
}

.play-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: opacity 0.3s;
}

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

.play-btn {
    width: 60px;
    height: 60px;
    background: rgba(255, 255, 255, 0.9);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #667eea;
    font-size: 1.5rem;
}

.video-info {
    padding: 1.5rem;
}

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

.video-desc {
    color: #666;
    font-size: 0.9rem;
    margin-bottom: 1rem;
}

.video-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.8rem;
    color: #999;
}

.stats-section {
    background: white;
    padding: 60px 0;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    text-align: center;
}

.stat-item {
    padding: 2rem;
}

.stat-number {
    font-size: 3rem;
    font-weight: bold;
    background: linear-gradient(45deg, #667eea, #764ba2);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    margin-bottom: 0.5rem;
}

.stat-label {
    color: #666;
    font-size: 1.1rem;
}

.faq-section {
    background: #f8f9fa;
    padding: 80px 0;
}

.faq-list {
    max-width: 800px;
    margin: 3rem auto 0;
}

.faq-item {
    background: white;
    margin-bottom: 1rem;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.faq-question {
    padding: 1.5rem;
    background: white;
    border: none;
    width: 100%;
    text-align: left;
    font-size: 1.1rem;
    font-weight: 600;
    color: #333;
    cursor: pointer;
    transition: background 0.3s;
}

.faq-question:hover {
    background: #f8f9fa;
}

.faq-answer {
    padding: 0 1.5rem 1.5rem;
    color: #666;
    line-height: 1.6;
    display: none;
}

footer {
    background: #333;
    color: white;
    padding: 3rem 0 1rem;
    text-align: center;
}

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

.footer-section h3 {
    color: #667eea;
    margin-bottom: 1rem;
}

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

.footer-section a:hover {
    color: #667eea;
}

.footer-bottom {
    border-top: 1px solid #555;
    padding-top: 1rem;
    color: #999;
}

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

@media (max-width: 768px) {
    .hero h1 {
        font-size: 2.5rem;
    }
    
    .hero .subtitle {
        font-size: 1.2rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    
    .nav-links {
        display: none;
    }
    
    .features-grid,
    .download-cards,
    .video-grid {
        grid-template-columns: 1fr;
    }
    
    .container {
        padding: 0 15px;
    }
}