body {
  margin: 0;
  background: #000;
  overflow: hidden;
  color: #3f3;
  font-family: monospace;
}

canvas {
  display: block;
  filter: drop-shadow(0 0 5px #3f3);
}

#ui {
  position: absolute;
  top: 10px;
  left: 10px;
  pointer-events: none;
  z-index: 10;
}