:root {
  --bg: #0f172a;
  --card: #111827;
  --text: #e5e7eb;
  --muted: #94a3b8;
  --accent: #f59e0b;
  --accent-2: #f97316;
  --border: rgba(255,255,255,.08);
}

* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: Arial, Helvetica, sans-serif;
  background: radial-gradient(circle at top, #1e293b, var(--bg));
  color: var(--text);
  min-height: 100vh;
}
.app {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
}
.card {
  width: min(100%, 560px);
  background: rgba(17,24,39,.92);
  border: 1px solid var(--border);
  border-radius: 24px;
  padding: 32px;
  box-shadow: 0 20px 60px rgba(0,0,0,.35);
}
.badge {
  display: inline-block;
  padding: 8px 12px;
  border-radius: 999px;
  background: rgba(245,158,11,.12);
  color: #fbbf24;
  font-size: 12px;
  letter-spacing: .08em;
  text-transform: uppercase;
}
h1 { margin: 16px 0 8px; font-size: 40px; }
p { margin: 0 0 24px; color: var(--muted); line-height: 1.5; }
.form { display: grid; gap: 12px; }
label { font-size: 14px; color: #cbd5e1; }
input, button {
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 14px 16px;
  font-size: 16px;
}
input {
  background: #0b1220;
  color: var(--text);
}
button {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #111827;
  font-weight: 700;
  cursor: pointer;
}
button:disabled {
  opacity: .7;
  cursor: wait;
}
.result {
  margin-top: 20px;
  padding: 16px;
  border-radius: 14px;
  background: rgba(255,255,255,.04);
  border: 1px solid var(--border);
}
.spinner {
  display: inline-block;
  width: 14px;
  height: 14px;
  border: 2px solid rgba(255,255,255,.25);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin .8s linear infinite;
  vertical-align: -2px;
  margin-right: 8px;
}
.result small { color: var(--muted); }
.hidden { display: none; }

@keyframes spin {
  to { transform: rotate(360deg); }
}