:root{
  --bg:#f7f8fb;
  --card:#ffffff;
  --text:#111827;
  --muted:#6b7280;
  --primary:#2563eb;
  --primary-weak:#e0e7ff;
  --danger:#ef4444;
  --ok:#059669;
  --border:#e5e7eb;
  --shadow:0 10px 25px rgba(0,0,0,.06);
  --radius:18px;
}
.cubic-solver{font:16px/1.6 system-ui,-apple-system,Segoe UI,Roboto,Ubuntu,Cantarell,Noto Sans,sans-serif;color:var(--text)}
.cubic-solver .container{margin:16px auto;padding:0 8px}
.cubic-solver .card{background:var(--card);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow);padding:18px}
.cubic-solver header{display:flex;gap:16px;align-items:center;justify-content:space-between;margin-bottom:12px}
.cubic-solver h1{font-size:clamp(20px,3.2vw,30px);margin:0}
.cubic-solver .sub{color:var(--muted);margin-top:4px}
.cubic-solver .grid{display:grid;gap:14px}
@media(min-width:720px){
  .cubic-solver .grid.cols-3{grid-template-columns:repeat(3,1fr)}
}
.cubic-solver label{display:block;font-weight:600;margin-bottom:6px}
.cubic-solver input[type="number"], .cubic-solver select {width:100%;padding:12px 14px;border:1px solid var(--border);border-radius:12px;background:#fff;color:var(--text);outline:none}
.cubic-solver input[type="number"]:focus, .cubic-solver select:focus{border-color:var(--primary);box-shadow:0 0 0 4px var(--primary-weak)}
.cubic-solver .row{display:flex;gap:12px;flex-wrap:wrap;align-items:center}
.cubic-solver .btn{appearance:none;border:none;border-radius:12px;padding:12px 16px;font-weight:700;cursor:pointer}
.cubic-solver .btn.primary{background:var(--primary);color:#fff}
.cubic-solver .btn.ghost{background:#fff;border:1px solid var(--border);color:var(--text)}
.cubic-solver .btn:disabled{opacity:.6;cursor:not-allowed}
.cubic-solver .pill{display:inline-flex;align-items:center;gap:8px;padding:8px 12px;border:1px solid var(--border);border-radius:999px;background:#fff}
.cubic-solver .muted{color:var(--muted)}
.cubic-solver .note{font-size:14px;color:var(--muted)}
.cubic-solver .results{display:grid;gap:14px}
.cubic-solver .result-item{background:#fafafa;border:1px dashed var(--border);border-radius:12px;padding:12px}
.cubic-solver .tag{display:inline-block;font-size:12px;padding:2px 8px;border-radius:999px;border:1px solid var(--border);background:#fff;color:var(--muted)}
.cubic-solver .ok{color:var(--ok)}
.cubic-solver .danger{color:var(--danger)}
.cubic-solver details{border:1px solid var(--border);border-radius:12px;padding:12px;background:#fff}
.cubic-solver summary{cursor:pointer;font-weight:700}
.cubic-solver footer{margin:16px 0;color:var(--muted);text-align:center}
.cubic-solver .kbd{font-family:ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,monospace;background:#f3f4f6;border:1px solid var(--border);border-bottom-width:2px;border-radius:6px;padding:2px 6px}
.cubic-solver .badge{background:var(--primary-weak);color:#1f2937;padding:6px 10px;border-radius:999px;font-size:12px;border:1px solid #c7d2fe}