:root {
  --bg: #ffffff;
  --text: #1a1a2e;
  --muted: #5c5c72;
  --accent: #4f46e5;
  --border: #e5e5ef;
  --callout-bg: #f5f5fb;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #0d0d1a;
    --text: #ececf4;
    --muted: #a0a0b8;
    --accent: #8b83ff;
    --border: #26263a;
    --callout-bg: #16162a;
  }
}
* { box-sizing: border-box; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  line-height: 1.65;
  -webkit-text-size-adjust: 100%;
}
main {
  max-width: 720px;
  margin: 0 auto;
  padding: 2rem 1.25rem 4rem;
}
h1 { font-size: 1.75rem; line-height: 1.25; margin: 0.5rem 0 0.25rem; }
h2 { font-size: 1.2rem; margin-top: 2.25rem; border-bottom: 1px solid var(--border); padding-bottom: 0.35rem; }
a { color: var(--accent); }
.meta { color: var(--muted); font-size: 0.9rem; margin-bottom: 1.5rem; }
.brand {
  display: inline-block;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--accent);
  text-decoration: none;
  margin-bottom: 1rem;
}
.callout {
  background: var(--callout-bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 0.9rem 1.1rem;
  font-size: 0.92rem;
  color: var(--muted);
  margin: 1.25rem 0;
}
ul { padding-left: 1.3rem; }
li { margin: 0.35rem 0; }
footer {
  max-width: 720px;
  margin: 0 auto;
  padding: 1.5rem 1.25rem 3rem;
  color: var(--muted);
  font-size: 0.85rem;
  border-top: 1px solid var(--border);
}
footer a { color: var(--muted); }