:root {
  --bg: #fbfaf5;
  --text: #1f2a1f;
  --muted: #5b665b;
  --accent: #3f7d3a;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #161a16;
    --text: #e6ebe4;
    --muted: #a3ad9f;
    --accent: #8fcf86;
  }
}
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 17px/1.6 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}
main {
  max-width: 40rem;
  margin: 0 auto;
  padding: 2.5rem 16px 4rem;
}
h1 { font-size: 2rem; margin: 0.5rem 0 0.25rem; }
h2 { font-size: 1.15rem; margin-top: 2rem; }
.lede { color: var(--muted); margin-top: 0; }
a { color: var(--accent); }
code { font-size: 0.95em; }
button {
  font: inherit;
  font-weight: 600;
  padding: 0.7rem 1.4rem;
  border: 0;
  border-radius: 999px;
  background: var(--accent);
  color: var(--bg);
  cursor: pointer;
}
button:disabled { opacity: 0.5; cursor: default; }