body {
  background: #6a2bff;
  color: #fff;
  width: 100%;
  height: 100vh;
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  overflow: hidden;
  cursor: -webkit-grab;
  cursor: -moz-grab;
}

canvas {
  width: 100%;
  height: 100%;
}