:root {
  --bg: #fbfaf7;
  --surface: #ffffff;
  --text: #1d1d1f;
  --muted: #5b5b63;
  --line: #e4e2dc;
  --accent: #2f6f4f;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #141517;
    --surface: #1c1d20;
    --text: #ececee;
    --muted: #a3a3ab;
    --line: #2e2f33;
    --accent: #7cc79f;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

main {
  max-width: 720px;
  margin: 0 auto;
  padding: 40px 16px 64px;
}

header { margin-bottom: 32px; }
header p { margin: 4px 0 0; color: var(--muted); }

h1 { font-size: 2rem; line-height: 1.2; margin: 0; }
h2 { font-size: 1.25rem; margin: 32px 0 8px; }

a { color: var(--accent); }

.card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 20px;
  margin-top: 16px;
}

.card h2 { margin-top: 0; }

ul { padding-left: 20px; }

nav { margin-top: 12px; display: flex; gap: 16px; flex-wrap: wrap; }

footer {
  margin-top: 48px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.9rem;
}