body {
  margin: 0;
  padding: 0;
}

#display {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;

  height: 66.67vw;
  width: 100vw;

  max-width: 150vh;
  max-height: 100vh;

  background-color: beige;

  margin: auto;
}