:root{--bg:#f6f7f9;--surface:#fff;--fg:#14181f;--muted:#5c6572;--line:#e1e4ea;--accent:#2b6cb0}
@media (prefers-color-scheme:dark){:root{--bg:#0f1218;--surface:#171b23;--fg:#eceff4;--muted:#9aa4b2;--line:#2a303b;--accent:#7db3f0}}
*{box-sizing:border-box}body{margin:0;background:var(--bg);color:var(--fg);font:16px/1.65 system-ui,-apple-system,Segoe UI,Roboto,sans-serif}
header{background:var(--surface);border-bottom:1px solid var(--line)}header div{max-width:760px;margin:0 auto;padding:14px 20px;display:flex;justify-content:space-between;gap:12px;align-items:center;flex-wrap:wrap}
header a{color:var(--fg);font-weight:700;text-decoration:none}header nav a{font-weight:500;color:var(--muted);margin-inline-start:16px;font-size:14px}
main{max-width:760px;margin:0 auto;padding:28px 20px 60px}h1{font-size:30px;line-height:1.2;margin:0 0 6px}h2{font-size:19px;margin:30px 0 6px}p,li{color:var(--fg)}ul,ol{padding-inline-start:22px}li{margin:4px 0}
.up{color:var(--muted);font-size:14px;margin:0 0 20px}a{color:var(--accent)}.box{background:var(--surface);border:1px solid var(--line);border-radius:12px;padding:14px 18px;margin:18px 0}
.btn{display:inline-block;background:var(--accent);color:#fff;border-radius:10px;padding:10px 16px;text-decoration:none;font-weight:600}
footer{max-width:760px;margin:0 auto;padding:0 20px 40px;color:var(--muted);font-size:14px}footer a{color:var(--muted);margin-inline-end:16px}