body {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  background: #111;
  color: white;
  font-family: sans-serif;
  margin: 0;
  flex-direction: column;
}
canvas {
  background: #222;
  border: 2px solid #fff;
  cursor: pointer;
}
p {
  margin-top: 10px;
}
button {
  margin-top: 10px;
  padding: 10px 20px;
  font-size: 16px;
  cursor: pointer;
}