:root {
  --bg: #fafaf9;
  --surface: #ffffff;
  --text: #1c1917;
  --muted: #57534e;
  --line: #e7e5e4;
  --accent: #4f46e5;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #121212;
    --surface: #1c1c1e;
    --text: #f5f5f4;
    --muted: #a8a29e;
    --line: #2e2e30;
    --accent: #a5b4fc;
  }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
a { color: var(--accent); }
.wrap { max-width: 880px; margin: 0 auto; padding: 0 16px; }
.top { border-bottom: 1px solid var(--line); background: var(--surface); }
.top .wrap { display: flex; align-items: center; justify-content: space-between; height: 60px; }
.brand { font-weight: 700; font-size: 1.15rem; color: var(--text); text-decoration: none; letter-spacing: -0.01em; }
nav a { color: var(--muted); text-decoration: none; margin-left: 16px; }
nav a:hover, nav a[aria-current] { color: var(--text); }
.hero { padding: 56px 0 24px; }
.hero h1 { font-size: clamp(1.8rem, 4vw, 2.6rem); line-height: 1.15; margin: 0 0 16px; letter-spacing: -0.02em; }
.lede { font-size: 1.15rem; color: var(--muted); margin: 0; max-width: 62ch; }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 16px; margin: 32px 0; }
.card { background: var(--surface); border: 1px solid var(--line); border-radius: 12px; padding: 20px; }
.card h2 { font-size: 1.05rem; margin: 0 0 8px; }
.card p { margin: 0; color: var(--muted); }
.note { margin: 32px 0; }
.note h2 { font-size: 1.1rem; margin: 0 0 6px; }
.note p { margin: 0; color: var(--muted); }
.prose { padding: 40px 16px 24px; }
.prose h1 { font-size: 2rem; margin: 0 0 4px; }
.prose h2 { font-size: 1.2rem; margin: 32px 0 8px; }
.prose p, .prose li { max-width: 70ch; }
.prose ul { padding-left: 20px; }
.meta { color: var(--muted); margin-top: 0; }
.foot { border-top: 1px solid var(--line); margin-top: 48px; padding: 20px 0; color: var(--muted); font-size: 0.9rem; }