.overlay {
  position: absolute;
  top: 0;
  bottom: 0;
  right: 0;
  left: 0;
  z-index: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  text-shadow:1px 0 0 white,0 1px 0 white,-1px 0 0 white,0 -1px 0 white;
}