body {
  text-align: center;
  font-family: Arial, sans-serif;
  background-color: #111;
  color: white;
}

canvas {
  display: block;
  margin: 20px auto;
  background-color: #000;
  border: 3px solid #fff;
}

button {
  padding: 10px 20px;
  font-size: 16px;
  margin-top: 20px;
  cursor: pointer;
}