body {
  margin: 0;
  background: black;
  font-family: 'Arial', sans-serif;
  text-align: center;
  color: white;
}
h1 {
  margin: 10px;
}
canvas {
  border: 2px solid white;
  display: block;
  margin: 0 auto;
  background: black;
}
#langBtn {
  position: absolute;
  top: 10px;
  right: 10px;
  background: #333;
  color: white;
  border: none;
  padding: 5px 10px;
  cursor: pointer;
}