:root {
  --bg: #f7f8fb;
  --surface: #ffffff;
  --surface-2: #f1f3f8;
  --ink: #0f172a;
  --ink-2: #334155;
  --muted: #64748b;
  --line: #e3e7ef;
  --accent: #2f5bea;
  --accent-ink: #ffffff;
  --accent-soft: #e8eefe;
  --tip: #0f7a55;
  --tip-soft: #e7f6ef;
  --warn: #a15c00;
  --warn-soft: #fdf3e2;
  --code-bg: #0f172a;
  --code-ink: #e2e8f0;
  --hero-a: #eef2ff;
  --hero-b: #f7f8fb;
  --shadow: 0 1px 2px rgba(15, 23, 42, .04), 0 4px 16px rgba(15, 23, 42, .05);
  --radius: 14px;
  --font: "Inter", ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b1020;
    --surface: #121a2e;
    --surface-2: #18223a;
    --ink: #e8ecf5;
    --ink-2: #c3cad9;
    --muted: #8b95aa;
    --line: #243049;
    --accent: #7c9cff;
    --accent-ink: #0b1020;
    --accent-soft: #1c2950;
    --tip: #5fd3a3;
    --tip-soft: #0f2a22;
    --warn: #f0b765;
    --warn-soft: #2d2213;
    --code-bg: #070b16;
    --hero-a: #141e3d;
    --hero-b: #0b1020;
    --shadow: 0 1px 2px rgba(0, 0, 0, .3);
  }
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 84px; }
body { margin: 0; background: var(--bg); color: var(--ink); font: 16px/1.6 var(--font); -webkit-font-smoothing: antialiased; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
img, svg { flex-shrink: 0; }
h1, h2, h3 { line-height: 1.25; letter-spacing: -.015em; }
:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; border-radius: 4px; }
.wrap { width: 100%; max-width: 1180px; margin: 0 auto; padding: 0 16px; }
@media (min-width: 720px) { .wrap { padding: 0 28px; } }
.skip { position: absolute; left: -9999px; }
.skip:focus { left: 16px; top: 12px; z-index: 10; background: var(--surface); padding: 8px 12px; border-radius: 8px; }

/* top bar */
.topbar { position: sticky; top: 0; z-index: 5; background: color-mix(in srgb, var(--surface) 88%, transparent); backdrop-filter: saturate(1.4) blur(10px); border-bottom: 1px solid var(--line); }
.topbar-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; gap: 16px; }
.brand { display: inline-flex; align-items: center; gap: 10px; color: var(--ink); font-weight: 600; white-space: nowrap; }
.brand:hover { text-decoration: none; }
.brand b { font-weight: 600; color: var(--muted); }
.mark { display: inline-grid; place-items: center; width: 32px; height: 32px; border-radius: 9px; background: var(--accent); color: var(--accent-ink); font-size: 12px; font-weight: 800; letter-spacing: .02em; }
.topnav { display: flex; align-items: center; gap: 22px; font-size: 14px; }
.topnav a { color: var(--ink-2); }
.topnav a:not(.btn-sm) { display: none; }
@media (min-width: 720px) { .topnav a:not(.btn-sm) { display: inline; } }
.btn-sm { padding: 7px 14px; border-radius: 9px; background: var(--ink); color: var(--bg) !important; font-weight: 600; }
.btn-sm:hover { text-decoration: none; opacity: .9; }
@media (max-width: 420px) { .brand b { display: none; } }

/* hero */
.hero { background: radial-gradient(1200px 400px at 50% -10%, var(--hero-a), var(--hero-b)); border-bottom: 1px solid var(--line); padding: 64px 0 56px; text-align: center; }
.hero h1 { font-size: clamp(30px, 5vw, 46px); margin: 6px 0 10px; }
.eyebrow { margin: 0; color: var(--accent); font-weight: 600; font-size: 13px; letter-spacing: .08em; text-transform: uppercase; }
.lead { color: var(--muted); font-size: 18px; margin: 0 0 8px; }
.hints { margin: 18px 0 0; color: var(--muted); font-size: 14px; display: flex; gap: 8px; justify-content: center; flex-wrap: wrap; align-items: center; }
.hints a { padding: 3px 10px; border: 1px solid var(--line); border-radius: 99px; background: var(--surface); color: var(--ink-2); }
.hints a:hover { border-color: var(--accent); color: var(--accent); text-decoration: none; }
.subhero { background: linear-gradient(var(--hero-a), var(--hero-b)); border-bottom: 1px solid var(--line); padding: 28px 0 32px; }
.subhero h1 { font-size: clamp(26px, 4vw, 34px); margin: 0 0 4px; }
.subhero-row { display: flex; gap: 16px; align-items: center; margin: 12px 0 22px; }
.subhero .search { margin: 0; max-width: 620px; }

/* search */
.search { position: relative; display: flex; align-items: center; gap: 10px; max-width: 640px; margin: 26px auto 0; padding: 0 14px; height: 50px; background: var(--surface); border: 1px solid var(--line); border-radius: 12px; box-shadow: var(--shadow); color: var(--muted); text-align: left; }
.search:focus-within { border-color: var(--accent); box-shadow: 0 0 0 4px var(--accent-soft); }
.search-lg { height: 60px; padding: 0 18px; border-radius: 14px; }
.search input { flex: 1; min-width: 0; border: 0; outline: 0; background: transparent; color: var(--ink); font: inherit; font-size: 16px; }
.search-lg input { font-size: 17px; }
.search kbd { font: 12px var(--mono); padding: 2px 7px; border: 1px solid var(--line); border-radius: 6px; color: var(--muted); }
@media (max-width: 560px) { .search kbd { display: none; } }
.results { position: absolute; left: 0; right: 0; top: calc(100% + 8px); background: var(--surface); border: 1px solid var(--line); border-radius: 12px; box-shadow: 0 12px 40px rgba(15, 23, 42, .16); overflow: hidden; z-index: 6; max-height: 420px; overflow-y: auto; }
.results a, .results p { display: block; padding: 12px 16px; color: var(--ink); border-bottom: 1px solid var(--line); margin: 0; }
.results a:last-child { border-bottom: 0; }
.results a:hover, .results a[aria-selected="true"] { background: var(--surface-2); text-decoration: none; }
.results small, .result small { display: block; color: var(--muted); font-size: 13px; }
.results p { color: var(--muted); font-size: 14px; }
mark { background: var(--accent-soft); color: inherit; border-radius: 3px; padding: 0 1px; }

/* sections & cards */
.section { padding: 48px 0 8px; }
.section-title { font-size: 20px; margin: 0 0 18px; }
.cards { display: grid; gap: 16px; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); }
.card { display: flex; flex-direction: column; gap: 6px; padding: 22px; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); color: var(--ink); transition: border-color .15s, transform .15s; }
.card:hover { text-decoration: none; border-color: var(--accent); transform: translateY(-2px); }
.card-icon { display: inline-grid; place-items: center; width: 42px; height: 42px; border-radius: 11px; background: var(--accent-soft); color: var(--accent); margin-bottom: 8px; }
.card-icon.lg { width: 54px; height: 54px; border-radius: 14px; margin: 0; }
.card-title { font-weight: 650; font-size: 17px; }
.card-desc { color: var(--muted); font-size: 14px; flex: 1; }
.card-meta { display: inline-flex; align-items: center; gap: 6px; margin-top: 10px; color: var(--accent); font-size: 13px; font-weight: 600; }

.article-list { list-style: none; margin: 0; padding: 0; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); overflow: hidden; }
.article-list li + li { border-top: 1px solid var(--line); }
.article-list a { display: block; padding: 16px 20px; color: var(--ink); font-weight: 550; }
.article-list a:hover { background: var(--surface-2); text-decoration: none; }
.article-list small { display: block; font-weight: 400; color: var(--muted); font-size: 14px; margin-top: 2px; }
@media (min-width: 800px) {
  .article-list.two-col { display: grid; grid-template-columns: 1fr 1fr; }
  .article-list.two-col li + li { border-top: 0; }
  .article-list.two-col li { border-bottom: 1px solid var(--line); }
  .article-list.two-col li:nth-child(odd) { border-right: 1px solid var(--line); }
}

.contact { display: flex; flex-wrap: wrap; gap: 16px 20px; align-items: center; margin: 48px 0 64px; padding: 24px; background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); }
.contact > div:first-child { display: grid; place-items: center; width: 46px; height: 46px; border-radius: 12px; background: var(--accent-soft); color: var(--accent); }
.contact > div:nth-child(2) { flex: 1; min-width: 220px; }
.contact h2 { margin: 0; font-size: 18px; }
.contact p { margin: 2px 0 0; color: var(--muted); font-size: 15px; }
.btn { display: inline-block; padding: 11px 18px; border-radius: 10px; background: var(--accent); color: var(--accent-ink); font-weight: 600; font-size: 15px; overflow-wrap: anywhere; }
.btn:hover { text-decoration: none; filter: brightness(1.07); }

/* article */
.crumbs { display: flex; flex-wrap: wrap; gap: 8px; font-size: 14px; color: var(--muted); }
.crumbs a { color: var(--muted); }
.article-layout { display: grid; gap: 40px; padding-top: 32px; padding-bottom: 64px; grid-template-columns: minmax(0, 1fr); }
@media (min-width: 1000px) { .article-layout { grid-template-columns: 250px minmax(0, 1fr); } }
@media (min-width: 1240px) { .article-layout { grid-template-columns: 250px minmax(0, 1fr) 200px; } }
.sidenav, .toc { font-size: 14px; }
.sidenav { display: none; }
.toc { display: none; }
@media (min-width: 1000px) { .sidenav { display: block; position: sticky; top: 88px; align-self: start; max-height: calc(100vh - 100px); overflow-y: auto; } }
@media (min-width: 1240px) { .toc { display: block; position: sticky; top: 88px; align-self: start; } }
.sidenav .search { margin: 0 0 22px; height: 42px; box-shadow: none; }
.sidenav .search kbd { display: none; }
.sidenav-title { margin: 20px 0 8px; font-size: 12px; font-weight: 700; letter-spacing: .06em; text-transform: uppercase; color: var(--muted); }
.sidenav ul, .toc ul { list-style: none; margin: 0; padding: 0; }
.sidenav a, .toc a { display: block; padding: 6px 10px; border-radius: 8px; color: var(--ink-2); }
.sidenav a:hover, .toc a:hover { background: var(--surface-2); text-decoration: none; }
.sidenav a[aria-current="page"] { background: var(--accent-soft); color: var(--accent); font-weight: 600; }
.toc a { border-left: 2px solid var(--line); border-radius: 0; padding: 4px 12px; }
.toc a.active { border-color: var(--accent); color: var(--accent); }
.article { min-width: 0; max-width: 760px; }
.article h1 { font-size: clamp(28px, 4vw, 36px); margin: 12px 0 8px; }
.prose { margin-top: 28px; color: var(--ink-2); font-size: 16.5px; }
.prose h2 { color: var(--ink); font-size: 23px; margin: 40px 0 12px; padding-top: 8px; }
.prose h3 { color: var(--ink); font-size: 18px; margin: 28px 0 8px; }
.prose p, .prose ul, .prose ol { margin: 0 0 16px; }
.prose li { margin: 6px 0; }
.prose ol { padding-left: 22px; }
.prose ol li::marker { color: var(--accent); font-weight: 700; }
.prose strong { color: var(--ink); }
.prose code { font: .88em var(--mono); background: var(--surface-2); border: 1px solid var(--line); padding: 1px 6px; border-radius: 6px; overflow-wrap: anywhere; }
.code { position: relative; margin: 0 0 18px; }
.code pre { margin: 0; padding: 16px 18px; padding-right: 72px; background: var(--code-bg); color: var(--code-ink); border-radius: 12px; overflow-x: auto; font: 13.5px/1.6 var(--mono); }
.code pre code { background: none; border: 0; padding: 0; color: inherit; font: inherit; }
.copy { position: absolute; top: 10px; right: 10px; padding: 4px 10px; border-radius: 7px; border: 1px solid rgba(255, 255, 255, .18); background: var(--code-bg); box-shadow: -14px 0 12px var(--code-bg); color: #e2e8f0; font: 12px var(--font); cursor: pointer; }
.copy:hover { border-color: rgba(255, 255, 255, .4); }
.table { overflow-x: auto; margin: 0 0 18px; border: 1px solid var(--line); border-radius: 12px; }
table { border-collapse: collapse; width: 100%; font-size: 15px; background: var(--surface); }
.table code { white-space: nowrap; overflow-wrap: normal; }
th, td { text-align: left; padding: 10px 14px; border-bottom: 1px solid var(--line); vertical-align: top; }
th { background: var(--surface-2); color: var(--ink); font-weight: 600; font-size: 14px; }
tr:last-child td { border-bottom: 0; }
.callout { margin: 0 0 18px; padding: 14px 16px; border-radius: 12px; border: 1px solid var(--line); border-left: 4px solid var(--accent); background: var(--accent-soft); }
.callout p { margin: 0; }
.callout p + p { margin-top: 8px; }
.callout-tip { border-left-color: var(--tip); background: var(--tip-soft); }
.callout-important { border-left-color: var(--warn); background: var(--warn-soft); }
.feedback { display: flex; flex-wrap: wrap; align-items: center; gap: 10px; margin-top: 44px; padding: 18px 0; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); color: var(--ink-2); font-size: 15px; }
.feedback button { padding: 6px 16px; border-radius: 8px; border: 1px solid var(--line); background: var(--surface); color: var(--ink); font: inherit; cursor: pointer; }
.feedback button:hover { border-color: var(--accent); color: var(--accent); }
.pager { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin-top: 24px; }
.pager a { display: block; padding: 14px 16px; border: 1px solid var(--line); border-radius: 12px; background: var(--surface); color: var(--ink); font-weight: 550; font-size: 15px; }
.pager a:hover { border-color: var(--accent); text-decoration: none; }
.pager small { display: block; color: var(--muted); font-weight: 400; font-size: 13px; }
.pager .next { text-align: right; }

/* search page */
.result { display: block; padding: 18px 20px; background: var(--surface); border: 1px solid var(--line); border-radius: 12px; margin-bottom: 12px; color: var(--ink); }
.result:hover { border-color: var(--accent); text-decoration: none; }
.result strong { font-size: 17px; }
.result p { margin: 6px 0 0; color: var(--ink-2); font-size: 15px; }
.empty { color: var(--muted); }

/* footer */
.footer { border-top: 1px solid var(--line); background: var(--surface); font-size: 14px; }
.footer-inner { display: grid; gap: 28px; padding-top: 36px; padding-bottom: 24px; grid-template-columns: 1fr; }
@media (min-width: 800px) { .footer-inner { grid-template-columns: 2fr 1fr 1fr; } }
.footer p { color: var(--muted); max-width: 320px; }
.footer-links { display: flex; flex-direction: column; gap: 8px; }
.footer-links a { color: var(--ink-2); overflow-wrap: anywhere; }
.footer-legal { padding-bottom: 28px; color: var(--muted); font-size: 13px; }

/* Developer band on the home page */
.dev-band { display: grid; gap: 24px; align-items: center; margin: 8px 0 8px; padding: 28px; background: var(--surface); border: 1px solid var(--line); border-radius: 16px; box-shadow: var(--shadow); }
@media (min-width: 900px) { .dev-band { grid-template-columns: 1fr 1fr; padding: 36px; } }
.dev-band h2 { margin: 4px 0 8px; font-size: 24px; }
.dev-band p { color: var(--ink-2); margin: 0 0 10px; }
.dev-band .eyebrow { margin: 0; }
.dev-links { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 18px; margin-top: 16px !important; }
.dev-code { margin: 0; min-width: 0; }
.dev-code pre { margin: 0; }