:root{--primary-color:#e74c3c;--secondary-color:#3498db;--text-color:#333;--bg-color:#f5f5f5;--card-bg:#fff;--border-color:#ddd;--hover-bg:#f0f0f0;--shadow:0 2px 8px rgba(0,0,0,0.1)}*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,"PingFang SC","Hiragino Sans GB","Microsoft YaHei",sans-serif;line-height:1.6;color:var(--text-color);background:var(--bg-color);font-size:16px}a{color:inherit;text-decoration:none;transition:color 0.3s}a:hover{color:var(--primary-color)}img{max-width:100%;height:auto;display:block}ul,ol{list-style:none}nav{background:var(--card-bg);box-shadow:var(--shadow);position:sticky;top:0;z-index:100}nav ul{display:flex;flex-wrap:nowrap;justify-content:space-between;align-items:center;max-width:1200px;margin:0 auto;padding:0}nav li{flex:1 1 0;min-width:0;text-align:center}nav a{display:block;padding:1rem 0.5rem;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;font-weight:500;transition:background 0.3s}nav a:hover,nav a[aria-current="page"]{background:var(--hover-bg);color:var(--primary-color)}@media (max-width:767px){nav ul{flex-wrap:nowrap;overflow-x:visible}nav li{flex:1 1 0;min-width:0}nav a{font-size:14px;padding:0.8rem 0.3rem}}.breadcrumb{max-width:1200px;margin:1rem auto;padding:0.5rem 1rem;font-size:14px;color:#666}.breadcrumb a{color:var(--secondary-color);text-decoration:underline}.breadcrumb span{color:#999}main{max-width:1200px;margin:2rem auto;padding:0 1rem}h1{font-size:2rem;margin-bottom:1rem;color:var(--text-color);font-weight:700}h2{font-size:1.5rem;margin:2rem 0 1rem;color:var(--text-color);font-weight:600}h3{font-size:1.25rem;margin:1.5rem 0 0.75rem;color:var(--text-color);font-weight:600}section{margin-bottom:3rem;background:var(--card-bg);padding:2rem;border-radius:8px;box-shadow:var(--shadow)}.card-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:1.5rem;margin-top:1.5rem}@media (max-width:768px){.card-grid{grid-template-columns:repeat(auto-fill,minmax(150px,1fr));gap:1rem}}.card{background:var(--card-bg);border:1px solid var(--border-color);border-radius:8px;overflow:hidden;transition:transform 0.3s,box-shadow 0.3s}.card:hover{transform:translateY(-5px);box-shadow:0 4px 12px rgba(0,0,0,0.15)}.card-image{width:100%;height:180px;background:linear-gradient(135deg,#667eea 0%,#764ba2 100%);display:flex;align-items:center;justify-content:center;color:white;font-size:1.5rem;font-weight:bold}.card-content{padding:1rem}.card-title{font-size:1.1rem;font-weight:600;margin-bottom:0.5rem;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.card-meta{font-size:0.85rem;color:#666;margin-bottom:0.5rem}.card-desc{font-size:0.9rem;color:#555;line-height:1.5;display:-webkit-box;-webkit-line-clamp:3;-webkit-box-orient:vertical;overflow:hidden}.card-tags{margin-top:0.75rem;display:flex;flex-wrap:wrap;gap:0.5rem}.tag{display:inline-block;padding:0.25rem 0.5rem;background:var(--hover-bg);border-radius:4px;font-size:0.75rem;color:#666}.video-list{list-style:none}.video-item{background:var(--card-bg);border:1px solid var(--border-color);border-radius:8px;padding:1.5rem;margin-bottom:1rem;transition:box-shadow 0.3s}.video-item:hover{box-shadow:var(--shadow)}.video-item h3{margin-top:0}.detail-container{background:var(--card-bg);border-radius:8px;padding:2rem;box-shadow:var(--shadow)}.detail-header{border-bottom:2px solid var(--border-color);padding-bottom:1rem;margin-bottom:2rem}.detail-meta{display:flex;flex-wrap:wrap;gap:1rem;margin:1rem 0;font-size:0.9rem;color:#666}.detail-meta>div{background:var(--hover-bg);padding:0.5rem 1rem;border-radius:4px}.detail-section{margin:2rem 0}.detail-section h2{font-size:1.3rem;margin-bottom:1rem;color:var(--primary-color)}.detail-section p{line-height:1.8;margin-bottom:1rem}.related-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(250px,1fr));gap:1rem;margin-top:1rem}@media (max-width:768px){.related-grid{grid-template-columns:1fr}}.related-item{background:var(--card-bg);border:1px solid var(--border-color);border-radius:6px;padding:1rem;transition:box-shadow 0.3s}.related-item:hover{box-shadow:var(--shadow)}.related-item h4{margin-bottom:0.5rem;font-size:1rem}.related-item p{font-size:0.85rem;color:#666;line-height:1.4}.intro-section{background:linear-gradient(135deg,#667eea 0%,#764ba2 100%);color:white;padding:3rem 2rem;border-radius:8px;margin-bottom:2rem;text-align:center}.intro-section h1{color:white;margin-bottom:1.5rem}.intro-section p{font-size:1.1rem;line-height:1.8;max-width:800px;margin:0 auto}.btn{display:inline-block;padding:0.75rem 1.5rem;background:var(--primary-color);color:white;border-radius:4px;font-weight:500;transition:background 0.3s}.btn:hover{background:#c0392b;color:white}.error-page{text-align:center;padding:4rem 2rem}.error-page h1{font-size:4rem;color:var(--primary-color);margin-bottom:1rem}.error-page p{font-size:1.2rem;color:#666;margin-bottom:2rem}@media (max-width:768px){main{margin:1rem auto;padding:0 0.5rem}section{padding:1rem}h1{font-size:1.5rem}h2{font-size:1.25rem}.detail-container{padding:1rem}.intro-section{padding:2rem 1rem}.intro-section p{font-size:1rem}}.text-center{text-align:center}.mt-1{margin-top:0.5rem}.mt-2{margin-top:1rem}.mt-3{margin-top:1.5rem}.mb-1{margin-bottom:0.5rem}.mb-2{margin-bottom:1rem}.mb-3{margin-bottom:1.5rem}