:root{
  --bg:#f7f8fb; --surface:#ffffff; --text:#1a2030; --muted:#566074; --line:#dfe3ec;
  --brand:#2f4fd8; --brand-ink:#ffffff; --brand-soft:#e8edff; --note:#fff7e0; --note-line:#f0d98a;
  --radius:12px; --maxw:820px;
}
@media (prefers-color-scheme: dark){
  :root{ --bg:#0f1320; --surface:#171c2e; --text:#e8ebf5; --muted:#a3adc4; --line:#2a3250;
    --brand:#8da2ff; --brand-ink:#0f1320; --brand-soft:#212a4f; --note:#2b2614; --note-line:#6b5a1e; }
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{margin:0;background:var(--bg);color:var(--text);
  font:16px/1.65 system-ui,-apple-system,"Segoe UI",Roboto,"Helvetica Neue",Arial,sans-serif}
a{color:var(--brand);text-underline-offset:2px}
a:focus-visible,.btn:focus-visible{outline:3px solid var(--brand);outline-offset:2px;border-radius:4px}
.skip{position:absolute;left:-999px;top:0;background:var(--brand);color:var(--brand-ink);padding:.6rem 1rem;z-index:10}
.skip:focus{left:8px;top:8px}
.wrap{max-width:var(--maxw);margin:0 auto;padding:0 20px}
header.site{background:var(--surface);border-bottom:1px solid var(--line)}
header.site .wrap{display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap;padding-top:14px;padding-bottom:14px}
.brand{display:flex;align-items:center;gap:10px;font-weight:700;color:var(--text);text-decoration:none;letter-spacing:.2px}
.brand .mark{width:30px;height:30px;border-radius:8px;background:var(--brand);color:var(--brand-ink);display:grid;place-items:center;font-size:13px;font-weight:800}
nav a{margin-left:18px;color:var(--muted);text-decoration:none;font-weight:600;font-size:.95rem}
nav a:hover,nav a[aria-current="page"]{color:var(--text);text-decoration:underline}
main{padding:36px 0 56px}
.hero{padding:28px 0 8px}
h1{font-size:clamp(1.9rem,5vw,2.7rem);line-height:1.15;margin:0 0 12px;letter-spacing:-.5px}
h2{font-size:1.35rem;margin:2.2rem 0 .6rem;line-height:1.3}
h3{font-size:1.05rem;margin:1.4rem 0 .3rem}
p{margin:.6rem 0}
.lead{font-size:1.15rem;color:var(--muted);max-width:60ch}
.actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:20px}
.btn{display:inline-block;padding:.65rem 1.1rem;border-radius:10px;font-weight:650;text-decoration:none;border:1px solid var(--brand)}
.btn.primary{background:var(--brand);color:var(--brand-ink)}
.btn.ghost{color:var(--brand);background:transparent}
.grid{display:grid;gap:16px;grid-template-columns:repeat(auto-fit,minmax(230px,1fr));margin-top:14px}
.card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:18px 18px 16px}
.card h3{margin-top:0}
.card p{color:var(--muted);margin-bottom:0}
.note{background:var(--note);border:1px solid var(--note-line);border-radius:var(--radius);padding:12px 16px;margin:18px 0}
.tablewrap{overflow-x:auto;border:1px solid var(--line);border-radius:var(--radius);background:var(--surface)}
table{border-collapse:collapse;width:100%;min-width:560px;font-size:.95rem}
th,td{text-align:left;padding:10px 14px;border-bottom:1px solid var(--line);vertical-align:top}
th{background:var(--brand-soft);font-weight:700}
tr:last-child td{border-bottom:0}
code{font:.88em ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;background:var(--brand-soft);padding:.1em .35em;border-radius:5px;word-break:break-all}
ul{padding-left:1.2rem}
li{margin:.3rem 0}
.toc{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:12px 18px;margin:18px 0}
.toc ol{margin:.3rem 0;padding-left:1.2rem;columns:2;column-gap:28px}
@media (max-width:560px){.toc ol{columns:1}}
.meta{color:var(--muted);font-size:.92rem}
footer.site{border-top:1px solid var(--line);background:var(--surface);color:var(--muted);font-size:.9rem}
footer.site .wrap{padding-top:22px;padding-bottom:26px}
footer.site a{margin-right:14px}
@media (max-width:560px){nav a{margin-left:0;margin-right:14px}header.site .wrap{align-items:flex-start;flex-direction:column;gap:6px}}
@media (prefers-reduced-motion:no-preference){.btn{transition:transform .08s ease}.btn:hover{transform:translateY(-1px)}}