body {
  margin: 0px;
  padding: 0px;
  height: 100vh;
  width: 100vw;
  overflow: hidden;
}

main {
    text-align: center;
    width: 100%;
}

canvas {
  display: block;
    margin: auto;
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
}