body {
  margin: 0;
  width: 100vw;
  height: 100vh;
  background-color: black;
}

model-viewer {
  width: 100vw;
  height: 100vh;
}

.overlay {
  position: absolute;
  right: 0;
  bottom: 0;
  width: 180px;
  height: 100px;
  z-index: 10;
  background: black;
}