:root { --bg:#ffffff; --fg:#1a1a1f; --muted:#5b5b66; --accent:#3b6cf6; --card:#f4f5f8; }
@media (prefers-color-scheme: dark) {
  :root { --bg:#111216; --fg:#ececf1; --muted:#a0a0ad; --accent:#7c9cff; --card:#1c1d23; }
}
* { box-sizing:border-box; }
body { margin:0; background:var(--bg); color:var(--fg); font:16px/1.6 system-ui,-apple-system,"Segoe UI",Roboto,sans-serif; }
main { max-width:760px; margin:0 auto; padding:40px 16px 64px; }
h1 { font-size:2rem; margin:0 0 4px; }
h2 { font-size:1.15rem; margin:28px 0 6px; }
p, li { color:var(--fg); }
.muted { color:var(--muted); }
a { color:var(--accent); }
.card { background:var(--card); border-radius:12px; padding:16px 20px; margin:16px 0; }
nav { display:flex; gap:16px; margin-bottom:28px; font-size:.95rem; }
footer { margin-top:48px; font-size:.9rem; color:var(--muted); }