:root{
  --bg:#f4f6fb; --surface:#ffffff; --text:#1a1f2b; --muted:#6b7280;
  --border:#e9edf5; --primary:#3d6dcc; --secondary:#2bb6a3;
}
@media (prefers-color-scheme: dark){
  :root{ --bg:#0f1116; --surface:#1a1d25; --text:#f2f4f8; --muted:#98a2b3; --border:#2a2f3a; }
}
*{box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{
  margin:0; background:var(--bg); color:var(--text);
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Helvetica,Arial,sans-serif;
  line-height:1.65; font-size:16px;
}
.wrap{max-width:820px; margin:0 auto; padding:24px 20px 64px}
header.top{display:flex; align-items:center; gap:14px; padding:22px 0}
.logo{width:52px;height:52px;border-radius:16px;background:linear-gradient(135deg,var(--primary),var(--secondary));
  display:flex;align-items:center;justify-content:center;color:#fff;font-size:26px;flex:0 0 auto}
.brand h1{font-size:20px;margin:0;font-weight:800;letter-spacing:-.4px}
.brand p{margin:2px 0 0;color:var(--muted);font-size:13px}
.card{background:var(--surface);border:1px solid var(--border);border-radius:20px;padding:28px 26px;margin-top:18px;
  box-shadow:0 8px 28px rgba(26,43,77,.05)}
h2{font-size:26px;font-weight:800;letter-spacing:-.5px;margin:.2em 0 .1em}
h3{font-size:17px;font-weight:700;margin:1.6em 0 .3em;color:var(--primary)}
.updated{color:var(--muted);font-size:13px;margin-bottom:6px}
p,li{color:var(--text)}
.muted{color:var(--muted)}
a{color:var(--primary);text-decoration:none}
a:hover{text-decoration:underline}
ul{padding-left:20px}
li{margin:.3em 0}
.nav{display:flex;gap:10px;flex-wrap:wrap;margin-top:20px}
.btn{display:inline-block;padding:12px 18px;border-radius:14px;font-weight:700;font-size:14px;
  background:var(--primary);color:#fff}
.btn.alt{background:transparent;border:1px solid var(--border);color:var(--text)}
footer{color:var(--muted);font-size:13px;text-align:center;padding:28px 0 8px}
.hero{text-align:center;padding:26px 0 6px}
.hero .logo{width:88px;height:88px;border-radius:26px;font-size:44px;margin:0 auto 16px}
.hero h2{font-size:32px}
.features{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:14px;margin-top:20px}
.feature{background:var(--surface);border:1px solid var(--border);border-radius:16px;padding:18px}
.feature b{display:block;margin-bottom:4px}
.note{background:rgba(247,162,59,.12);border:1px solid rgba(247,162,59,.35);border-radius:12px;padding:12px 14px;font-size:14px;margin-top:14px}