:root {
  color-scheme: dark;
  --bg: #0d1117;
  --card: #161b22;
  --ink: #e6edf3;
  --muted: #8b949e;
  --accent: #58a6ff;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: Inter, system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
  background: radial-gradient(circle at top, #1c2737, var(--bg));
  color: var(--ink);
  min-height: 100vh;
  display: grid;
  place-items: center;
}

.app {
  width: min(92vw, 520px);
  background: color-mix(in srgb, var(--card) 90%, black);
  border: 1px solid #30363d;
  border-radius: 20px;
  padding: 24px;
  text-align: center;
  box-shadow: 0 20px 45px rgba(0,0,0,.35);
}

h1 { margin: 0 0 6px; font-size: clamp(1.4rem, 3vw, 2rem); }
.subtitle { margin: 0 0 18px; color: var(--muted); }

.puck {
  width: 280px;
  max-width: 100%;
  aspect-ratio: 1/1;
  border-radius: 50%;
  border: 10px solid #0a0a0a;
  background: radial-gradient(circle at 30% 20%, #4f5d75, #111 62%);
  color: white;
  font-weight: 700;
  font-size: 1.1rem;
  padding: 24px;
  display: grid;
  place-items: center;
  margin: 0 auto 14px;
  cursor: pointer;
  transition: transform .2s ease;
}
.puck:active { transform: scale(.98); }

.puck.shaking {
  animation: shake .55s ease;
}

@keyframes shake {
  0%, 100% { transform: translateX(0) rotate(0deg); }
  25% { transform: translateX(-8px) rotate(-4deg); }
  50% { transform: translateX(8px) rotate(3deg); }
  75% { transform: translateX(-5px) rotate(-2deg); }
}

.actions {
  display: flex;
  gap: 10px;
  justify-content: center;
  flex-wrap: wrap;
}

button {
  border-radius: 10px;
  border: 1px solid #30363d;
  background: #21262d;
  color: var(--ink);
  padding: 10px 14px;
  font-weight: 600;
}
button:hover { border-color: var(--accent); }

.hint {
  margin-top: 14px;
  color: var(--muted);
  font-size: .9rem;
}