:root{--bg:#f6f8fa;--bg-card:#fff;--bg-input:#f0f3f6;--border:#d0d7de;--text:#1f2328;--text-dim:#656d76;--accent:#0969da;--green:#1a7f37;--danger:#cf222e;--warning:#9a6700;--max-w:1280px}*{box-sizing:border-box;margin:0;padding:0}html{font-size:16px}body{background:var(--bg);color:var(--text);min-height:100vh;font-family:Inter,system-ui,sans-serif;line-height:1.6}.topnav{border-bottom:1px solid var(--border);backdrop-filter:blur(8px);z-index:100;background:#fffffff2;justify-content:space-between;align-items:center;padding:12px 24px;display:flex;position:sticky;top:0}.nav-brand{color:var(--text);align-items:center;gap:8px;font-size:.95rem;font-weight:700;text-decoration:none;display:flex}.nav-breadcrumb{color:var(--text-dim);align-items:center;gap:6px;font-size:.82rem;display:flex}.nav-breadcrumb a{color:var(--accent);text-decoration:none}.page-header{background:var(--bg-card,#fff);border-bottom:1px solid var(--border);padding:36px 24px}.header-inner{max-width:var(--max-w);flex-direction:column;gap:10px;margin:0 auto;display:flex}.header-badge{color:var(--accent);letter-spacing:.03em;background:#0969da14;border:1px solid #0969da33;border-radius:12px;align-self:flex-start;padding:3px 10px;font-size:.72rem;font-weight:700}.page-header h1{color:var(--text);letter-spacing:-.02em;font-size:2.1rem;font-weight:800}.header-desc{color:var(--text-dim);max-width:860px;font-size:1.02rem;line-height:1.55}.header-meta{color:var(--text-dim);flex-wrap:wrap;gap:20px;margin-top:4px;font-size:.82rem;display:flex}.page-main{max-width:var(--max-w);flex-direction:column;gap:32px;margin:0 auto;padding:24px;display:flex}.author-note{background:var(--bg-card,#fff);border:1px solid var(--border);border-radius:8px;align-items:flex-start;gap:16px;padding:16px 20px;display:flex}.an-avatar{width:42px;height:42px;color:var(--bg-card,#fff);background:linear-gradient(135deg,#0969da,#1a7f37);border-radius:50%;flex-shrink:0;justify-content:center;align-items:center;font-size:.95rem;font-weight:700;display:flex}.an-content{color:var(--text);flex-direction:column;gap:6px;font-size:.88rem;line-height:1.5;display:flex}.an-content a{color:var(--accent);text-decoration:none}.content-section{flex-direction:column;gap:16px;display:flex}.content-section h2{color:var(--text);font-size:1.35rem;font-weight:700}.formula-grid{grid-template-columns:repeat(auto-fit,minmax(260px,1fr));gap:16px;display:grid}.formula-card{background:var(--bg-card,#fff);border:1px solid var(--border);border-radius:8px;flex-direction:column;gap:8px;padding:18px;display:flex}.formula-icon{font-size:1.4rem}.formula-card h3{color:var(--text);font-size:.92rem;font-weight:700}.formula-block{background:var(--bg-input,#f6f8fa);border:1px solid var(--border);color:#0969da;border-radius:6px;padding:8px 12px;font-family:JetBrains Mono,monospace;font-size:.84rem;font-weight:600}.formula-card p{color:var(--text-dim);font-size:.82rem;line-height:1.45}.guide-content{background:var(--bg-card,#fff);border:1px solid var(--border);border-radius:8px;flex-direction:column;gap:12px;padding:20px;display:flex}.guide-content h3{font-size:1rem;font-weight:700}.guide-steps{color:var(--text);flex-direction:column;gap:10px;padding-left:20px;font-size:.88rem;display:flex}.related-grid{grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:14px;display:grid}.related-card{background:var(--bg-card,#fff);border:1px solid var(--border);color:inherit;border-radius:8px;align-items:center;gap:14px;padding:14px 16px;text-decoration:none;transition:all .15s;display:flex}.related-card:hover{border-color:var(--accent);box-shadow:0 2px 8px #0000000d}.rc-icon{font-size:1.6rem}.rc-title{color:var(--accent);font-size:.9rem;font-weight:600}.rc-desc{color:var(--text-dim);font-size:.78rem}.feedback-card{background:var(--bg-card,#fff);border:1px solid var(--border);border-radius:8px;flex-wrap:wrap;justify-content:space-between;align-items:center;gap:20px;padding:20px;display:flex}.fc-content h3{font-size:1rem;font-weight:700}.fc-content p{color:var(--text-dim);max-width:600px;margin-top:4px;font-size:.85rem}.btn{cursor:pointer;border-radius:6px;align-items:center;padding:9px 18px;font-size:.85rem;font-weight:600;text-decoration:none;display:inline-flex}.btn-primary{background:var(--accent);color:var(--bg-card,#fff);border:none}.btn-primary:hover{background:#0858b9}.page-footer{border-top:1px solid var(--border);background:var(--bg-card,#fff);margin-top:40px;padding:28px 24px}.footer-inner{max-width:var(--max-w);color:var(--text-dim);text-align:center;flex-direction:column;gap:6px;margin:0 auto;font-size:.8rem;display:flex}.footer-inner a{color:var(--accent)}[data-theme=dark]{--bg:#0d1117;--bg-card:#161b22;--bg-input:#0d1117;--border:#30363d;--text:#e6edf3;--text-dim:#8b949e;--accent:#58a6ff;--green:#2da44e;--danger:#ff7b72;--warning:#d29922;--bg-nav:#0d1117e6}