:root {
  --bg: #f5f8fc;
  --text: #172235;
  --muted: #55657a;
  --accent: #0b7a75;
  --card: #ffffff;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0b1220;
    --text: #f3f6fc;
    --muted: #9aa9bc;
    --accent: #55d6d0;
    --card: #111c2e;
  }
}
* {
  box-sizing: border-box;
}
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font:
    17px/1.6 -apple-system,
    BlinkMacSystemFont,
    'Segoe UI',
    Roboto,
    sans-serif;
}
main {
  max-width: 720px;
  margin: 0 auto;
  padding: 48px 16px 64px;
}
h1 {
  font-size: 32px;
  line-height: 1.2;
  margin: 0 0 8px;
}
h2 {
  font-size: 20px;
  margin: 32px 0 8px;
}
p,
li {
  color: var(--text);
}
.muted {
  color: var(--muted);
}
a {
  color: var(--accent);
}
ul {
  padding-left: 20px;
}
nav {
  margin-bottom: 32px;
}
nav a {
  margin-right: 16px;
  font-weight: 600;
  text-decoration: none;
}
.card {
  background: var(--card);
  border-radius: 16px;
  padding: 16px 20px;
}