:root{--bg:#f7f7f5;--fg:#1d1d1f;--muted:#6e6e73;--card:#fff;--line:#e3e3e0;--accent:#1f7a4d;--accent-fg:#fff;--code:#f0f0ec}
@media (prefers-color-scheme:dark){:root{--bg:#141414;--fg:#ececec;--muted:#a1a1a6;--card:#1e1e1e;--line:#333;--accent:#3fb37a;--accent-fg:#0b1f14;--code:#262626}}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);color:var(--fg);font:16px/1.55 -apple-system,BlinkMacSystemFont,"Segoe UI",Helvetica,Arial,sans-serif}
main{max-width:760px;margin:0 auto;padding:32px 16px 64px}
header{display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap;margin-bottom:28px}
header a.brand{font-weight:700;font-size:20px;color:var(--fg);text-decoration:none}
nav{display:flex;gap:16px;align-items:center;flex-wrap:wrap}
nav a{color:var(--muted);text-decoration:none}nav a:hover{color:var(--fg)}
button.lang{border:1px solid var(--line);background:var(--card);color:var(--fg);border-radius:6px;padding:4px 10px;cursor:pointer;font:inherit;font-size:14px}
h1{font-size:30px;line-height:1.2;margin:0 0 8px}h2{font-size:20px;margin:32px 0 8px}
p.lead{color:var(--muted);font-size:18px;margin:0 0 24px}
.card{background:var(--card);border:1px solid var(--line);border-radius:12px;padding:20px;margin:16px 0}
a.download{display:inline-block;background:var(--accent);color:var(--accent-fg);font-weight:600;text-decoration:none;padding:12px 22px;border-radius:10px;font-size:17px}
dl.meta{display:grid;grid-template-columns:max-content 1fr;gap:6px 16px;margin:16px 0 0;font-size:14px}
dl.meta dt{color:var(--muted)}dl.meta dd{margin:0;min-width:0}
code{background:var(--code);padding:1px 5px;border-radius:4px;font:13px/1.5 ui-monospace,SFMono-Regular,Menlo,monospace;overflow-wrap:anywhere}
ol,ul{padding-left:22px}li{margin:4px 0}
.muted{color:var(--muted);font-size:14px}
footer{margin-top:48px;color:var(--muted);font-size:14px}footer a{color:var(--muted)}
html[lang=vi] [lang=en]:not(html),html[lang=en] [lang=vi]:not(html){display:none}