:root{--bg:#fff;--fg:#1b1f23;--muted:#5b6470;--line:#e6e8eb;--accent:#0b7a5a}
@media (prefers-color-scheme:dark){:root{--bg:#121417;--fg:#e8eaed;--muted:#a0a8b3;--line:#2a2f35;--accent:#3cc497}}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);color:var(--fg);font:16px/1.65 system-ui,-apple-system,"Segoe UI","Noto Sans Bengali","Hind Siliguri",sans-serif}
main{max-width:760px;margin:0 auto;padding:40px 16px 64px}
h1{font-size:1.8rem;margin:0 0 .25rem}
h2{font-size:1.2rem;margin:2rem 0 .5rem}
p,li{color:var(--fg)}
.muted{color:var(--muted)}
a{color:var(--accent)}
hr{border:0;border-top:1px solid var(--line);margin:2.5rem 0}
nav{display:flex;gap:16px;margin-bottom:2rem;font-size:.95rem}