:root{
  --bg:#0f172a;
  --card:#111827;
  --muted:#94a3b8;
  --text:#e5e7eb;
  --accent:#22c55e;
  --warn:#ef4444;
  --ring:#3b82f6;
  --border:#1f2937;
}
*{box-sizing:border-box}
body{
  margin:0;
  font-family:ui-sans-serif,system-ui,-apple-system,Segoe UI,Roboto,Helvetica,Arial;
  background:#0e1327;
  color:var(--text);
  padding:24px;
}
.calc-wrap{max-width:960px;margin:0 auto;display:grid;gap:20px}
.card{background:var(--card);border:1px solid var(--border);border-radius:16px;padding:20px}
h1{font-size:28px;margin:0 0 6px 0}
p.lead{margin:0 0 14px 0;color:var(--muted)}
.grid{display:grid;gap:14px;grid-template-columns:repeat(12,1fr)}
.col-6{grid-column:span 12}
@media(min-width:720px){.col-6{grid-column:span 6}}
label{display:block;font-weight:600;margin:0 0 6px 0;font-size:14px;color:#cbd5e1}
.input{width:100%;padding:12px 14px;background:#0b1020;color:var(--text);border:1px solid #1e293b;border-radius:12px;font-size:16px}
.input:focus{border-color:var(--ring);box-shadow:0 0 0 3px rgba(59,130,246,.3)}
.hint{font-size:12px;color:var(--muted);margin-top:6px}
.row{display:flex;gap:10px;flex-wrap:wrap}
.btn{border:1px solid #243045;background:#111827;color:var(--text);padding:10px 14px;border-radius:12px;cursor:pointer;font-weight:600}
.btn.secondary{border-color:#2a364a}
.btn.accent{background:var(--accent);border-color:#16a34a;color:#06230f}
.results{display:grid;gap:12px;grid-template-columns:repeat(12,1fr)}
.metric{grid-column:span 12;background:#0b1020;border:1px solid #1f2a3d;border-radius:12px;padding:14px}
@media(min-width:720px){.metric{grid-column:span 4}}
.metric h3{margin:0 0 8px 0;font-size:13px;color:#9fb0c7;font-weight:700;text-transform:uppercase}
.value{font-size:22px;font-weight:700}
.ok{color:var(--accent)}
.bad{color:var(--warn)}
.warn-banner{margin-top:8px;padding:10px 12px;border-radius:10px;border:1px solid #3a1e23;background:#1c0f12;color:#f8d7da;font-size:13px}