:root {
  color-scheme: light dark;
  --paper: #f3f3f3;
  --ink: #111214;
  --muted: #5f6268;
  --line: #d7d7d7;
  --blue: #1674c8;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: -apple-system, BlinkMacSystemFont, "Helvetica Neue", Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
}

header, main, footer {
  width: min(calc(100% - 40px), 720px);
  margin: 0 auto;
}

header { padding: 28px 0; }

header a {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: inherit;
  text-decoration: none;
  font-weight: 750;
}

header img { width: 40px; height: 40px; }
main { padding: 64px 0 90px; }

h1 {
  margin: 0;
  font-size: clamp(2.8rem, 8vw, 4.8rem);
  line-height: .96;
  letter-spacing: -.055em;
}

h2 { margin: 42px 0 10px; font-size: 1.25rem; }
h3 { margin: 26px 0 8px; font-size: 1rem; }
p, li { color: var(--muted); font-size: 1rem; line-height: 1.65; }
ul { padding-left: 20px; }
a { color: var(--blue); }

.updated { margin-top: 18px; }
.important { color: var(--ink); font-weight: 650; }

footer {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding: 24px 0 36px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: .82rem;
}

footer nav { display: flex; flex-wrap: wrap; gap: 14px; }

@media (prefers-color-scheme: dark) {
  :root {
    --paper: #050607;
    --ink: #f5f6f7;
    --muted: #a7abb2;
    --line: #292c31;
    --blue: #45aff0;
  }
}

@media (max-width: 520px) {
  main { padding-top: 42px; }
  footer { flex-direction: column; }
}