:root {
  --bg: #ffffff;
  --ink: #111111;
  --muted: #6b6b6b;
  --rule: #e6e6e6;
  color-scheme: light dark;
}
@media (prefers-color-scheme: dark) {
  :root { --bg: #000000; --ink: #f2f2f2; --muted: #9e9e9e; --rule: #222222; }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font: 17px/1.6 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue", Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}
main { max-width: 640px; margin: 0 auto; padding: 56px 20px 80px; }
header { display: flex; align-items: center; gap: 14px; margin-bottom: 48px; }
header img { width: 44px; height: 44px; border-radius: 10px; }
header a { color: inherit; text-decoration: none; font-weight: 600; font-size: 20px; }
nav { margin-left: auto; display: flex; gap: 18px; font-size: 15px; }
nav a { color: var(--muted); font-weight: 400; font-size: 15px; }
nav a[aria-current="page"] { color: var(--ink); }
h1 { font-size: 40px; line-height: 1.15; letter-spacing: -0.02em; margin: 0 0 12px; }
h2 { font-size: 20px; margin: 40px 0 8px; }
p, li { color: var(--ink); }
.muted { color: var(--muted); }
.lead { font-size: 21px; color: var(--muted); margin: 0 0 32px; }
a { color: var(--ink); }
ul { padding-left: 20px; }
footer { margin-top: 64px; padding-top: 20px; border-top: 1px solid var(--rule); font-size: 14px; color: var(--muted); }
footer a { color: var(--muted); }
@media (max-width: 480px) {
  h1 { font-size: 32px; }
  header { flex-wrap: wrap; }
  nav { margin-left: 0; width: 100%; }
}