:root {
  --bg: #fafaf9;
  --text: #1c1917;
  --muted: #78716c;
  --link: #0f766e;
  --line: #e7e5e4;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #1c1917; --text: #f5f5f4; --muted: #a8a29e; --link: #5eead4; --line: #44403c; }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.6 system-ui, -apple-system, "Segoe UI", sans-serif;
}
main { max-width: 680px; margin: 0 auto; padding: 56px 16px 72px; }
h1 { font-size: 2rem; line-height: 1.2; margin: 0 0 8px; }
h2 { font-size: 1.15rem; margin: 40px 0 8px; }
.lead, .muted { color: var(--muted); }
a { color: var(--link); }
section { border-top: 1px solid var(--line); }
footer { margin-top: 48px; padding-top: 16px; border-top: 1px solid var(--line); font-size: 0.95rem; }