:root{--bg:#F3F5F9;--surface:#fff;--ink:#121826;--muted:#5A6477;--line:#D7DDE8;--accent:#0F766E}
@media (prefers-color-scheme:dark){:root:not([data-theme="light"]){--bg:#0F141E;--surface:#171E2B;--ink:#E6EBF3;--muted:#9AA5B8;--line:#2B3548;--accent:#2DD4BF}}
:root[data-theme="dark"]{--bg:#0F141E;--surface:#171E2B;--ink:#E6EBF3;--muted:#9AA5B8;--line:#2B3548;--accent:#2DD4BF}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);color:var(--ink);font:16px/1.6 system-ui,-apple-system,"Segoe UI",sans-serif}
main{max-width:720px;margin:0 auto;padding:40px 16px 64px}
h1{font:700 40px/1.05 "Arial Narrow",system-ui,sans-serif;letter-spacing:-.01em;margin:0 0 8px}
h2{font:700 22px/1.2 system-ui,sans-serif;margin:32px 0 8px}
p,li{color:var(--ink)}
.muted{color:var(--muted)}
a{color:var(--accent);font-weight:600}
.card{background:var(--surface);border:1px solid var(--line);border-radius:20px;padding:20px;margin:20px 0}
.brand{display:flex;align-items:center;gap:10px;font:700 24px system-ui,sans-serif;margin-bottom:24px}
.logo{width:28px;height:28px;border-radius:8px;background:var(--accent);display:inline-block}
footer{margin-top:40px;font-size:14px;color:var(--muted)}