:root{--fg:#172b4d;--muted:#44546f;--accent:#0c66e4;--bg:#fff;--line:#dcdfe4}
@media (prefers-color-scheme:dark){:root{--fg:#dee4ea;--muted:#9fadbc;--accent:#579dff;--bg:#1d2125;--line:#38414a}}
*{box-sizing:border-box}body{margin:0;font:16px/1.6 -apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,sans-serif;color:var(--fg);background:var(--bg)}
header{border-bottom:1px solid var(--line)}nav,main,footer{max-width:760px;margin:0 auto;padding:16px 20px}
nav a{margin-right:18px;color:var(--muted);text-decoration:none;font-weight:500}nav a.brand{color:var(--fg);font-weight:700}
a{color:var(--accent)}h1{font-size:1.9rem;line-height:1.25}h2{margin-top:2rem;font-size:1.3rem}code{background:rgba(127,127,127,.15);padding:1px 5px;border-radius:4px}
footer{color:var(--muted);font-size:.9rem;border-top:1px solid var(--line);margin-top:40px}