* {
  margin: 0;
  padding: 0;
}
html,
body {
  height: 100%;
  width: 100%;
  font-family: serif;
  overflow: hidden;
  position: relative;
}
canvas {
  display: block;
  height: 100%;
  width: 100%;
  position: absolute;
  top: 0;
  left: 0;
  z-index: -1;
}