:root{--bg:#f6f8f8;--fg:#1d2527;--muted:#5b6b6f;--accent:#0b7f8c;--card:#fff}
@media (prefers-color-scheme:dark){:root:not([data-theme="light"]){--bg:#111719;--fg:#e6eeef;--muted:#9fb0b3;--accent:#39b7c4;--card:#1a2225}}
:root[data-theme="dark"]{--bg:#111719;--fg:#e6eeef;--muted:#9fb0b3;--accent:#39b7c4;--card:#1a2225}
*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--fg);font:17px/1.55 -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,sans-serif}
main{max-width:720px;margin:0 auto;padding:32px 16px 64px}h1{font-size:30px;margin:.2em 0}h2{font-size:20px;margin-top:1.8em}
a{color:var(--accent)}.muted{color:var(--muted)}.card{background:var(--card);border-radius:14px;padding:16px 20px;margin:16px 0}
nav a{margin-right:16px}