:root {
  color-scheme: light dark;
  --ink: #1d1d1f;
  --muted: #6e6e73;
  --line: #d2d2d7;
  --paper: #ffffff;
  --accent: #0066cc;
}
@media (prefers-color-scheme: dark) {
  :root { --ink: #f5f5f7; --muted: #a1a1a6; --line: #3a3a3c; --paper: #000000; --accent: #2997ff; }
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font: 17px/1.55 -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue", Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}
main { max-width: 640px; margin: 0 auto; padding: 64px 24px 96px; }
header { display: flex; align-items: baseline; justify-content: space-between; margin-bottom: 48px; }
header a { color: var(--ink); text-decoration: none; font-weight: 600; letter-spacing: -0.01em; }
header nav a { color: var(--muted); font-weight: 400; margin-left: 20px; }
header nav a:hover { color: var(--accent); }
h1 { font-size: 40px; line-height: 1.1; letter-spacing: -0.02em; margin: 0 0 12px; }
h2 { font-size: 20px; letter-spacing: -0.01em; margin: 40px 0 8px; }
p { margin: 0 0 16px; }
.lede { font-size: 21px; color: var(--muted); margin-bottom: 40px; }
.muted { color: var(--muted); }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
kbd { font: 0.9em ui-monospace, "SF Mono", Menlo, monospace; padding: 1px 5px; border: 1px solid var(--line); border-radius: 5px; }
code { font: 0.92em ui-monospace, "SF Mono", Menlo, monospace; }
footer { margin-top: 72px; padding-top: 24px; border-top: 1px solid var(--line); color: var(--muted); font-size: 14px; }
footer a { color: var(--muted); margin-right: 16px; }
ul { padding-left: 20px; }
li { margin-bottom: 6px; }