/* Full-page alpha/testing overlay */
#alpha-overlay {
  position: fixed;
  inset: 0;
  z-index: 999999;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(15, 23, 42, 0.94); /* slate-900 w/ opacity */
  color: #f8fafc; /* slate-50 */
  backdrop-filter: blur(3px);
  font-family: system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
}
#alpha-overlay .alpha-box {
  width: min(92vw, 620px);
  border-radius: 16px;
  padding: 28px 22px;
  text-align: center;
  background: rgba(255,255,255,0.06);
  border: 1px solid rgba(255,255,255,0.18);
  box-shadow: 0 8px 40px rgba(0,0,0,.35);
}
#alpha-overlay h2 {
  margin: 0 0 10px;
  font-size: clamp(20px, 3.6vw, 28px);
}
#alpha-overlay p {
  margin: 0 0 14px;
  color: #cbd5e1; /* slate-300 */
  line-height: 1.45;
}
#alpha-overlay .row {
  display: flex;
  gap: 8px;
  justify-content: center;
  margin-top: 10px;
}
#alpha-overlay .btn {
  padding: 10px 14px;
  border-radius: 12px;
  border: 1px solid #e2e8f0;
  background: #fff;
  color: #0f172a;
  cursor: pointer;
}
#alpha-overlay .btn.ghost {
  background: transparent;
  color: #f8fafc;
  border-color: rgba(255,255,255,0.35);
}
#alpha-overlay input[type="password"] {
  padding: 10px 12px;
  border-radius: 10px;
  border: 1px solid #e2e8f0;
  background: #fff;
  color: #0f172a;
  width: 180px;
}