:root {
  color-scheme: light dark;
  --bg: #f5f5f7;
  --card: #ffffff;
  --text: #1d1d1f;
  --muted: #6e6e73;
  --link: #0071e3;
  --border: rgba(0,0,0,0.08);
  --max: 40rem;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #000000;
    --card: #1c1c1e;
    --text: #f5f5f7;
    --muted: #a1a1a6;
    --link: #2997ff;
    --border: rgba(255,255,255,0.12);
  }
}
* { box-sizing: border-box; }
html { font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, Helvetica, Arial, sans-serif; }
body { margin: 0; background: var(--bg); color: var(--text); line-height: 1.55; font-size: 17px; }
a { color: var(--link); text-decoration: none; }
a:hover { text-decoration: underline; }
header { border-bottom: 1px solid var(--border); background: var(--card); }
header .inner, main, footer .inner { max-width: var(--max); margin: 0 auto; padding: 1rem 1.25rem; }
header .brand { font-weight: 600; font-size: 1.1rem; color: var(--text); text-decoration: none; }
header nav { margin-top: 0.35rem; }
header nav a { color: var(--muted); margin-right: 1rem; font-size: 0.95rem; }
main { padding-top: 1.75rem; padding-bottom: 3rem; }
.card { background: var(--card); border: 1px solid var(--border); border-radius: 14px; padding: 1.5rem 1.35rem; }
h1 { font-size: 1.75rem; line-height: 1.2; margin: 0 0 0.5rem; letter-spacing: -0.02em; }
h2 { font-size: 1.2rem; margin: 1.75rem 0 0.5rem; letter-spacing: -0.01em; }
h3 { font-size: 1.05rem; margin: 1.25rem 0 0.4rem; }
.meta, .muted { color: var(--muted); font-size: 0.95rem; }
ul, ol { padding-left: 1.2rem; }
li { margin: 0.35rem 0; }
hr { border: none; border-top: 1px solid var(--border); margin: 1.5rem 0; }
footer { border-top: 1px solid var(--border); color: var(--muted); font-size: 0.9rem; padding-bottom: 2rem; }
.hero-actions { margin-top: 1.25rem; display: flex; flex-wrap: wrap; gap: 0.75rem; }
.btn { display: inline-block; padding: 0.65rem 1rem; border-radius: 980px; background: var(--link); color: #fff !important; text-decoration: none !important; font-weight: 500; font-size: 0.95rem; }
.btn.secondary { background: transparent; color: var(--link) !important; border: 1px solid var(--border); }
code { font-size: 0.9em; }