body {
  touch-action: manipulation;
  -webkit-user-select: none;
  -webkit-tap-highlight-color: transparent;
}
#tetris canvas {
  display: block;
  margin: 0 auto;
  padding: 10px;
  border-radius: 10px;
  border: 1px solid;
}
#tetris a {
  position: absolute;
  display: block;
  cursor: pointer;
}