:root {
  --ground: #f7f8fa; --text: #14181f; --muted: #5a6370; --rule: #dde1e7; --accent: #1f6feb;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --ground: #0b0e13; --text: #f3f5f8; --muted: #aeb6c2; --rule: #262c36; --accent: #7cc8ff;
  }
}
:root[data-theme="dark"] {
  --ground: #0b0e13; --text: #f3f5f8; --muted: #aeb6c2; --rule: #262c36; --accent: #7cc8ff;
}
* { box-sizing: border-box; }
body {
  margin: 0; background: var(--ground); color: var(--text);
  font: 17px/1.6 -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
}
main { max-width: 680px; margin: 0 auto; padding: 48px 16px 80px; }
nav { display: flex; gap: 20px; margin-bottom: 48px; font-size: 15px; }
nav a:first-child { font-weight: 700; color: var(--text); margin-right: auto; }
a { color: var(--accent); }
h1 { font-size: 34px; line-height: 1.2; margin: 0 0 8px; }
h2 { font-size: 21px; margin: 40px 0 8px; }
.lede { font-size: 20px; color: var(--muted); margin-top: 0; }
.muted, footer { color: var(--muted); }
footer { margin-top: 64px; padding-top: 16px; border-top: 1px solid var(--rule); font-size: 14px; }
li { margin-bottom: 6px; }