:root{--bg:#0a0a0f;--fg:#f7f7f7;--muted:#a9b0bb;--accent:#64c8ff;--gold:#d4af37}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);color:var(--fg);font:400 17px/1.7 ui-sans-serif,system-ui,-apple-system,Segoe UI,Roboto,Inter,Helvetica,Arial}
main{max-width:1100px;margin:0 auto;padding:24px}
a{color:var(--accent);text-decoration:none}a:hover{text-decoration:underline}
header.site{position:sticky;top:0;background:#0b0b12cc;backdrop-filter:blur(6px);border-bottom:1px solid #1e2633;z-index:10}
header.site .wrap{display:flex;gap:16px;align-items:center;justify-content:space-between;max-width:1100px;margin:0 auto;padding:12px 16px}
nav.top a{margin:0 10px;color:#cfe8ff;font-weight:600}
nav.top a.active{color:#fff;border-bottom:2px solid var(--accent)}
.footer{border-top:1px solid #1e2633;margin-top:48px;padding:24px 0;color:var(--muted);text-align:center}
figure{margin:24px auto;text-align:center}
figcaption{color:var(--muted);font-size:.95rem;margin-top:8px}
h1{font:700 42px/1.2 ui-serif,Georgia,Times,serif;margin:18px 0;color:#e8f4ff}
h2{font-size:28px;margin-top:36px;color:#cfe8ff;border-bottom:1px solid #223045;padding-bottom:6px;counter-increment:section}
h3{font-size:22px;margin-top:24px;color:#b8d8ff}
pre.equation,.equation-box{font:600 18px/1.5 ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;background:#0f1420;border-left:4px solid var(--accent);padding:16px;border-radius:8px;overflow:auto;color:#cfe8ff}
.toc{position:sticky;top:64px;max-height:calc(100vh - 80px);overflow:auto;border-left:1px solid #1e2633;padding-left:16px;margin-left:24px}
.layout{display:grid;grid-template-columns:1fr;gap:24px}
@media (min-width:1024px){.layout{grid-template-columns:3fr 1fr}}
.toc h4{margin:8px 0 12px 0;color:#9ecbfd}
.toc a{display:block;color:#9bb5cc;padding:4px 0}
hr{border:none;border-top:1px solid #1e2633;margin:32px 0}
blockquote{border-left:4px solid #2e3b55;margin:16px 0;padding:8px 16px;color:#b7c5d8;background:#0f1420}
table{width:100%;border-collapse:collapse;margin:16px 0;background:#0f1420}
th,td{border:1px solid #1e2633;padding:10px;text-align:left}
small.help{color:#9aa4b2}