body {
  margin: 0;
  padding: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  position: rerative;
}
canvas {
    overflow: hidden;
    position: fixed;
    top: 50%;
    left: 50%;
    z-index: -1;
    transform: translate(-50%, -50%);
    /* filter: drop-shadow(1px 1px 10px #c9c9c9); */
}