:root{--primary-color:#0066cc;--secondary-color:#ff6600;--text-color:#333;--text-light:#666;--text-lighter:#999;--bg-white:#ffffff;--bg-light:#f5f5f5;--bg-hover:#f8f9fa;--border-color:#e0e0e0;--shadow:0 2px 8px rgba(0,0,0,0.1);--shadow-hover:0 4px 12px rgba(0,0,0,0.15);--border-radius:8px;--transition:all 0.3s ease}*{margin:0;padding:0;box-sizing:border-box}body{font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif;line-height:1.6;color:var(--text-color);background-color:var(--bg-light);font-size:16px}a{color:var(--primary-color);text-decoration:none;transition:var(--transition)}a:hover{color:var(--secondary-color);text-decoration:none}ul,ol{list-style:none}img{max-width:100%;height:auto;display:block}.site-header{background:var(--bg-white);box-shadow:var(--shadow);position:sticky;top:0;z-index:100}.site-nav{display:flex;flex-wrap:nowrap;justify-content:space-between;align-items:center;max-width:1200px;margin:0 auto;padding:1rem}.site-nav a{flex:1 1 0;min-width:0;text-align:center;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;padding:0.5rem;font-size:14px;font-weight:500;border-radius:4px;transition:var(--transition)}.site-nav a:first-child{font-weight:700;color:var(--primary-color);font-size:16px}.site-nav a:hover{background:var(--bg-hover);color:var(--secondary-color);text-decoration:none}.breadcrumb{max-width:1200px;margin:1rem auto;padding:0 1rem;font-size:14px;color:var(--text-light)}.breadcrumb a{color:var(--primary-color);margin:0 0.5rem}.breadcrumb a:first-child{margin-left:0}.breadcrumb a:hover{text-decoration:underline}.container{max-width:1200px;margin:2rem auto;padding:0 1rem}.section{margin-bottom:3rem}.section-title{font-size:1.5rem;margin-bottom:1.5rem;border-left:4px solid var(--primary-color);padding-left:1rem;font-weight:600}.card{background:var(--bg-white);border-radius:var(--border-radius);padding:1.5rem;box-shadow:var(--shadow);transition:var(--transition)}.card:hover{box-shadow:var(--shadow-hover);transform:translateY(-2px)}.card h3{font-size:1.2rem;margin-bottom:0.5rem;font-weight:600}.card h3 a{color:var(--text-color)}.card h3 a:hover{color:var(--primary-color)}.card-meta{font-size:0.85rem;color:var(--text-light);margin-bottom:0.5rem}.card-tags{font-size:0.8rem;color:var(--text-lighter);margin-bottom:0.5rem}.card-desc{font-size:0.9rem;color:var(--text-color);line-height:1.5}.grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:1.5rem}.grid-2{grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:1rem}.tag{display:inline-block;background:#e8f4f8;color:var(--primary-color);padding:0.3rem 0.8rem;border-radius:4px;margin:0.2rem;font-size:0.85rem;transition:var(--transition)}.tag:hover{background:var(--primary-color);color:white}.btn{display:inline-block;background:var(--primary-color);color:white;padding:0.8rem 1.5rem;border-radius:4px;font-size:1rem;font-weight:500;text-align:center;transition:var(--transition);border:none;cursor:pointer}.btn:hover{background:var(--secondary-color);color:white;text-decoration:none;transform:translateY(-2px);box-shadow:var(--shadow)}.back-to-top{position:fixed;bottom:2rem;right:2rem;width:50px;height:50px;background:var(--primary-color);color:white;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:1.5rem;cursor:pointer;opacity:0;visibility:hidden;transition:var(--transition);box-shadow:var(--shadow);z-index:99}.back-to-top.show{opacity:1;visibility:visible}.back-to-top:hover{background:var(--secondary-color);transform:scale(1.1)}@media (max-width:768px){body{font-size:14px}.site-nav{padding:0.8rem}.site-nav a{font-size:12px;padding:0.3rem}.site-nav a:first-child{font-size:14px}.container{margin:1rem auto;padding:0 0.5rem}.section-title{font-size:1.3rem}.grid{grid-template-columns:1fr;gap:1rem}.card{padding:1rem}.back-to-top{bottom:1rem;right:1rem;width:40px;height:40px;font-size:1.2rem}}@media (max-width:480px){.breadcrumb{font-size:12px;margin:0.5rem auto}.card h3{font-size:1.1rem}}