html, body {
  margin: 0;
  padding: 0;
  overflow: hidden;
  display: flex;
  justify-content: center;
  align-items: center;
  height: 100vh;
  background: #f0f0f0;
}

canvas {
  display: block;
  touch-action: none;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}