*{margin:0;padding:0;box-sizing:border-box;}html{font-size:16px;-webkit-text-size-adjust:100%;}body{font-family:-apple-system,BlinkMacSystemFont,'Segoe UI','PingFang SC','Hiragino Sans GB','Microsoft YaHei',sans-serif;line-height:1.6;color:#333;background:#f5f5f5;min-height:100vh;display:flex;flex-direction:column;}a{text-decoration:none;color:inherit;transition:color 0.3s ease;}a:hover{color:#e74c3c;}img{max-width:100%;height:auto;display:block;}ul,ol{list-style:none;}.container{max-width:1200px;margin:0 auto;padding:0 20px;width:100%;}.site-header{background:linear-gradient(135deg,#667eea 0%,#764ba2 100%);color:white;padding:1rem 0;box-shadow:0 2px 10px 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li:last-child{color:#667eea;font-weight:500;}.main-content{flex:1;padding:2rem 0;}.home-section{background:white;border-radius:8px;padding:2rem;margin-bottom:2rem;box-shadow:0 2px 8px rgba(0,0,0,0.05);}.section-title{font-size:1.8rem;font-weight:bold;margin-bottom:1.5rem;padding-bottom:0.75rem;border-bottom:3px solid #667eea;color:#333;}.section-desc{font-size:1rem;line-height:1.8;color:#666;margin-bottom:1.5rem;}.section-features{display:grid;grid-template-columns:repeat(auto-fit,minmax(250px,1fr));gap:1.5rem;margin-top:1.5rem;}.feature-item{padding:1.5rem;background:#f9f9f9;border-radius:6px;border-left:4px solid #667eea;transition:transform 0.3s ease,box-shadow 0.3s ease;}.feature-item:hover{transform:translateY(-3px);box-shadow:0 4px 12px rgba(102,126,234,0.2);}.feature-item h3{font-size:1.2rem;margin-bottom:0.75rem;color:#667eea;}.feature-item p{font-size:0.95rem;color:#666;line-height:1.6;}.video-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:2rem;}.video-card{background:white;border-radius:8px;overflow:hidden;box-shadow:0 2px 8px rgba(0,0,0,0.05);transition:transform 0.3s ease,box-shadow 0.3s ease;}.video-card:hover{transform:translateY(-5px);box-shadow:0 6px 20px rgba(0,0,0,0.1);}.video-thumb{width:100%;height:180px;background:linear-gradient(135deg,#667eea 0%,#764ba2 100%);display:flex;align-items:center;justify-content:center;color:white;font-size:3rem;position:relative;}.video-info{padding:1.25rem;}.video-title{font-size:1.1rem;font-weight:bold;margin-bottom:0.75rem;color:#333;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden;}.video-meta{display:flex;flex-wrap:wrap;gap:0.75rem;margin-bottom:0.75rem;font-size:0.85rem;color:#999;}.video-meta span{display:flex;align-items:center;gap:0.25rem;}.video-desc{font-size:0.9rem;color:#666;line-height:1.6;display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden;margin-bottom:1rem;}.video-btn{display:inline-block;padding:0.6rem 1.5rem;background:linear-gradient(135deg,#667eea 0%,#764ba2 100%);color:white;border-radius:4px;font-size:0.9rem;font-weight:500;transition:all 0.3s ease;}.video-btn:hover{transform:translateX(3px);box-shadow:0 4px 12px rgba(102,126,234,0.4);}.video-detail{background:white;border-radius:8px;padding:2.5rem;box-shadow:0 2px 8px rgba(0,0,0,0.05);}.detail-header{margin-bottom:2rem;padding-bottom:2rem;border-bottom:2px solid #f0f0f0;}.detail-title{font-size:2.2rem;font-weight:bold;margin-bottom:1.5rem;color:#333;line-height:1.4;}.detail-meta{display:flex;flex-wrap:wrap;gap:1.5rem;font-size:0.95rem;color:#666;}.detail-meta-item{display:flex;align-items:center;gap:0.5rem;}.detail-meta-label{font-weight:600;color:#667eea;}.detail-tags{display:flex;flex-wrap:wrap;gap:0.5rem;margin-top:1rem;}.tag{padding:0.4rem 0.9rem;background:#f0f0f0;border-radius:20px;font-size:0.85rem;color:#666;transition:all 0.3s ease;}.tag:hover{background:#667eea;color:white;}.detail-section{margin-bottom:2rem;}.detail-section-title{font-size:1.4rem;font-weight:bold;margin-bottom:1rem;color:#333;padding-left:1rem;border-left:4px solid #667eea;}.detail-section-content{font-size:1rem;line-height:1.9;color:#555;text-align:justify;}.related-videos{margin-top:3rem;padding-top:2rem;border-top:2px solid #f0f0f0;}.related-title{font-size:1.6rem;font-weight:bold;margin-bottom:1.5rem;color:#333;}.related-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:1.5rem;}.related-item{padding:1rem;background:#f9f9f9;border-radius:6px;transition:all 0.3s ease;}.related-item:hover{background:#f0f0f0;transform:translateX(5px);}.related-item-title{font-size:1rem;font-weight:600;color:#333;margin-bottom:0.5rem;display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden;}.related-item-meta{font-size:0.85rem;color:#999;}.error-page{text-align:center;padding:4rem 2rem;}.error-code{font-size:8rem;font-weight:bold;color:#667eea;line-height:1;margin-bottom:1rem;}.error-message{font-size:1.5rem;color:#666;margin-bottom:2rem;}.error-links{display:flex;gap:1rem;justify-content:center;flex-wrap:wrap;}.error-link{padding:0.8rem 2rem;background:linear-gradient(135deg,#667eea 0%,#764ba2 100%);color:white;border-radius:4px;font-weight:500;transition:all 0.3s ease;}.error-link:hover{transform:translateY(-2px);box-shadow:0 4px 12px rgba(102,126,234,0.4);}.site-footer{background:#2c3e50;color:#ecf0f1;padding:2rem 0 1rem;margin-top:auto;}.footer-content{text-align:center;}.footer-nav{margin-bottom:1.5rem;}.footer-nav-list{display:flex;justify-content:center;gap:2rem;flex-wrap:wrap;}.footer-nav-list a:hover{color:#667eea;}.footer-info{font-size:0.9rem;color:#95a5a6;line-height:1.8;}.footer-info p{margin:0.5rem 0;}@media (max-width:768px){.container{padding:0 15px;}.header-content{flex-direction:column;gap:1rem;}.site-logo{margin-right:0;font-size:1.3rem;}.site-nav{width:100%;overflow-x:auto;overflow-y:hidden;-webkit-overflow-scrolling:touch;}.nav-list{gap:1rem;padding:0.5rem 0;justify-content:flex-start;}.nav-list li a{font-size:0.9rem;padding:0.4rem 0.8rem;}.video-grid{grid-template-columns:1fr;gap:1.5rem;}.section-features{grid-template-columns:1fr;}.detail-title{font-size:1.6rem;}.detail-meta{flex-direction:column;gap:0.75rem;}.error-code{font-size:5rem;}.footer-nav-list{flex-direction:column;gap:1rem;}}@media (max-width:480px){html{font-size:14px;}.home-section{padding:1.5rem;}.video-detail{padding:1.5rem;}.section-title{font-size:1.5rem;}}