:root {
  --text: #1d1d1f;
  --muted: #6e6e73;
  --background: #ffffff;
  --accent: #2f6fe4;
  --rule: #e5e5ea;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --text: #f5f5f7;
    --muted: #a1a1a6;
    --background: #161618;
    --accent: #6ea0ff;
    --rule: #2c2c2e;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--background);
  color: var(--text);
  font: 17px/1.55 -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
}

main {
  max-width: 720px;
  margin: 0 auto;
  padding: 48px 20px 64px;
}

header {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 32px;
}

header img { width: 56px; height: 56px; border-radius: 13px; }
header a { color: inherit; text-decoration: none; font-weight: 600; font-size: 20px; }

h1 { font-size: 34px; line-height: 1.15; margin: 0 0 8px; }
h2 { font-size: 21px; margin: 32px 0 8px; }
p, li { margin: 0 0 12px; }
ul { padding-left: 22px; }
a { color: var(--accent); }
.muted { color: var(--muted); }

footer {
  margin-top: 48px;
  padding-top: 16px;
  border-top: 1px solid var(--rule);
  color: var(--muted);
  font-size: 15px;
}

footer a { margin-right: 16px; }