/* Dark silver/gray/blue theme */
:root{
  --bg:#0f1115;
  --panel:#161a22;
  --panel-2:#1d2330;
  --text:#e6e6ea;
  --muted:#aab2c8;
  --primary:#3b6fe0;
  --primary-2:#5a8fff;
  --accent:#7aa2ff;
  --border:#2b3244;
  --silver:#c0c0c0;
}
*{box-sizing:border-box}
html,body{margin:0;padding:0;background:var(--bg);color:var(--text);font-family:Inter,system-ui,Segoe UI,Roboto,Arial,sans-serif;}
a{color:var(--accent);text-decoration:none}
a:hover{color:#fff}
.container{max-width:980px;margin:0 auto;padding:24px}
header.site{
  background:linear-gradient(180deg,#161a22 0%, #141824 100%);
  border-bottom:1px solid var(--border);
  position:sticky; top:0; z-index:10;
}
.brand{display:flex;align-items:center;gap:12px;justify-content:center;padding:14px 16px}
.brand h1{margin:0;font-size:22px;color:var(--silver);letter-spacing:.5px}
nav.primary{display:flex;gap:14px;flex-wrap:wrap;justify-content:center;padding:10px 16px;background:var(--panel-2);border-top:1px solid var(--border);border-bottom:1px solid var(--border)}
nav.primary a{padding:10px 12px;border-radius:8px;font-weight:600;color:#a0b8ff}
nav.primary a.active, nav.primary a:hover{background:var(--panel);color:#fff}
.card{background:var(--panel);border:1px solid var(--border);border-radius:14px;padding:20px;box-shadow:0 8px 22px rgba(0,0,0,.35)}
.grid{display:grid;gap:18px}
.grid.cols-2{grid-template-columns:repeat(auto-fit,minmax(260px,1fr))}
h2{margin-top:0;font-size:26px;color:#dfe6ff}
h3{color:#cfe0ff}
small, .muted{color:var(--muted)}
button, .btn, input[type=submit]{
  background:var(--primary);
  color:#fff;border:none;border-radius:10px;padding:10px 14px;font-weight:700;cursor:pointer;
  transition:transform .06s ease, background .2s ease;
}
button:hover,.btn:hover,input[type=submit]:hover{background:var(--primary-2);transform:translateY(-1px)}
input, textarea{
  width:100%;padding:12px 12px;border-radius:10px;background:var(--panel-2);border:1px solid var(--border);color:#fff;
}
label{display:block;margin:8px 0 6px 2px;color:#c7d3ff;font-weight:600}
form{display:grid;gap:12px}
.notice{padding:12px 14px;border-radius:12px;background:#0d1529;border:1px solid #20315f}
.footer{border-top:1px solid var(--border);padding:24px;text-align:center;color:var(--muted);background:#0f121b;margin-top:36px}
.code{font-family:ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,monospace;background:#0b0f19;padding:2px 6px;border-radius:6px;border:1px solid #222b42}
.alert{background:#1f2a44;border:1px solid #2c3a61;border-radius:12px;padding:14px}
ul.clean{margin:0 0 0 18px}