* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  position: relative;
  width: 100%;
  height: 100%;
}

canvas {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 1;
}

.ui-screen {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 2;
  width: 100%;
  height: 100%;

  pointer-events: auto;
}