@font-face { font-family: "Geist"; font-style: normal; font-weight: 100 900; font-display: swap; src: url("../assets/fonts/geist-latin.woff2") format("woff2"); }

:root {
  --bg: #f7f9fc;
  --surface: #ffffff;
  --ink: #1d1d1f;
  --ink-2: #424245;
  --muted: #6e6e73;
  --line: rgba(15, 23, 42, 0.08);
  --accent: #0a6cff;
  --accent-ink: #0050c8;
  --accent-soft: #e9f2ff;
  --wash: #dbe9ff;
  --shadow: 0 1px 2px rgba(16, 24, 40, 0.05), 0 12px 32px rgba(16, 24, 40, 0.07);
  --font: "Geist", -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", system-ui, sans-serif;
  color-scheme: light;
}
:root[data-theme="dark"] {
  --bg: #0a0e17;
  --surface: #111827;
  --ink: #f1f4f9;
  --ink-2: #c4cad6;
  --muted: #8a93a5;
  --line: rgba(255, 255, 255, 0.09);
  --accent: #3d8bff;
  --accent-ink: #9cc6ff;
  --accent-soft: rgba(61, 139, 255, 0.16);
  --wash: rgba(61, 139, 255, 0.14);
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.3), 0 12px 32px rgba(0, 0, 0, 0.3);
  color-scheme: dark;
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  min-height: 100dvh;
  background: radial-gradient(70% 420px at 50% -120px, var(--wash), transparent 70%), var(--bg);
  color: var(--ink);
  font: 400 16px/1.65 var(--font);
  -webkit-font-smoothing: antialiased;
}
a { color: var(--accent-ink); text-underline-offset: 3px; }
a:focus-visible, button:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 6px; }

.top {
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  max-width: 1040px; margin: 0 auto; padding: 22px 16px;
}
.brand { display: flex; align-items: center; gap: 10px; color: var(--ink); text-decoration: none; font-weight: 650; letter-spacing: -0.02em; }
.brand img { width: 34px; height: 34px; border-radius: 9px; }
.brand small { display: block; font-size: 12.5px; font-weight: 500; color: var(--muted); letter-spacing: 0; }
.back {
  display: inline-flex; align-items: center; gap: 6px;
  min-height: 40px; padding: 0 14px; border-radius: 999px;
  background: var(--surface); box-shadow: inset 0 0 0 1px var(--line), var(--shadow);
  color: var(--ink); font-size: 14px; font-weight: 550; text-decoration: none;
  transition: transform 0.2s cubic-bezier(0.32, 0.72, 0, 1);
}
.back:hover { transform: translateY(-1px); }
.back:active { transform: scale(0.97); }

.wrap {
  display: grid; grid-template-columns: 220px minmax(0, 1fr); gap: 48px;
  max-width: 1040px; margin: 0 auto; padding: 24px 16px 96px;
}
.toc { position: sticky; top: 24px; align-self: start; font-size: 14px; }
.toc p { margin: 0 0 10px; font-size: 12px; font-weight: 600; letter-spacing: 0.06em; text-transform: uppercase; color: var(--muted); }
.toc ol { margin: 0; padding: 0; list-style: none; counter-reset: t; }
.toc li { counter-increment: t; }
.toc a { display: flex; gap: 10px; padding: 6px 0; color: var(--ink-2); text-decoration: none; }
.toc li a::before { content: counter(t, decimal-leading-zero); color: var(--muted); font-variant-numeric: tabular-nums; }
.toc a:hover { color: var(--accent-ink); }
.pages { margin-top: 24px; padding-top: 16px; border-top: 1px solid var(--line); display: grid; gap: 0; }
.pages a { padding: 5px 0; }
.pages a[aria-current="page"] { color: var(--accent-ink); font-weight: 600; }

article {
  padding: 40px clamp(20px, 5vw, 56px) 48px;
  border-radius: 24px; background: var(--surface);
  box-shadow: inset 0 0 0 1px var(--line), var(--shadow);
}
.eyebrow { margin: 0 0 8px; font-size: 13px; font-weight: 600; color: var(--accent-ink); }
h1 { margin: 0; font-size: clamp(32px, 5vw, 44px); line-height: 1.08; font-weight: 700; letter-spacing: -0.035em; }
.updated { margin: 10px 0 0; font-size: 14px; color: var(--muted); }
.lede { margin: 22px 0 0; font-size: 18px; color: var(--ink-2); }
.free {
  display: flex; gap: 12px; align-items: flex-start;
  margin: 26px 0 0; padding: 16px 18px; border-radius: 16px;
  background: var(--accent-soft); color: var(--ink);
}
.free svg { flex: none; margin-top: 3px; color: var(--accent); }
section { padding-top: 36px; scroll-margin-top: 24px; }
h2 { display: flex; gap: 12px; align-items: baseline; margin: 0 0 10px; font-size: 21px; line-height: 1.3; font-weight: 650; letter-spacing: -0.02em; }
h2 span { font-size: 14px; font-weight: 600; color: var(--accent-ink); font-variant-numeric: tabular-nums; }
p, li { color: var(--ink-2); }
section p { margin: 0 0 12px; }
ul { margin: 0 0 12px; padding-left: 22px; }
li { margin: 4px 0; }
li::marker { color: var(--accent); }
b, strong { color: var(--ink); font-weight: 600; }
.foot { max-width: 1040px; margin: 0 auto; padding: 0 16px 40px; font-size: 13px; color: var(--muted); }

@media (max-width: 820px) {
  .wrap { grid-template-columns: minmax(0, 1fr); gap: 20px; padding-top: 8px; }
  .toc { position: static; }
  .toc ol, .pages { display: none; }
  .toc p { display: none; }
  article { padding: 28px 20px 36px; border-radius: 20px; }
}
@media (prefers-reduced-motion: reduce) { .back { transition: none; } }