* { box-sizing: border-box; font-family: system-ui, -apple-system, Segoe UI, Roboto, sans-serif; }
body {
  margin: 0;
  min-height: 100vh;
  display: grid;
  place-items: center;
  background: radial-gradient(circle at top, #0f172a, #020617);
  color: #e2e8f0;
}
main { text-align: center; padding: 16px; }
canvas {
  width: min(90vw, 480px);
  height: auto;
  border: 2px solid #334155;
  border-radius: 10px;
  background: linear-gradient(#0b1024, #020617);
  box-shadow: 0 12px 30px rgba(0,0,0,.35);
}
p { margin: 8px 0; color: #94a3b8; font-size: 14px; }
.controls {
  margin-top: 10px;
  display: flex;
  justify-content: center;
  gap: 12px;
}
.controls button {
  border: 0;
  border-radius: 12px;
  padding: 10px 18px;
  font-size: 24px;
  background: #1e293b;
  color: #fff;
}
.controls button:active {
  transform: scale(0.96);
  background: #334155;
}