:root {
  --bg: #fbfaf7;
  --text: #1f2328;
  --muted: #5b6168;
  --rule: #e3e0d8;
  --link: #1d5fa8;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #16181b;
    --text: #e6e6e3;
    --muted: #a0a4a9;
    --rule: #2c3035;
    --link: #7fb2ec;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}
main {
  max-width: 680px;
  margin: 0 auto;
  padding: 48px 16px 64px;
}
h1 { font-size: 1.7rem; line-height: 1.25; margin: 0 0 4px; }
h2 { font-size: 1.1rem; margin: 32px 0 6px; }
p, li { margin: 0 0 12px; }
ul { padding-left: 22px; }
.sub { color: var(--muted); margin-bottom: 28px; }
a { color: var(--link); }
footer {
  margin-top: 40px;
  padding-top: 16px;
  border-top: 1px solid var(--rule);
  color: var(--muted);
  font-size: 0.9rem;
}
footer a { margin-right: 16px; }