.debugtooltip
  {
  visibility: hidden;
  position: absolute;
  top: 0;
  left: 0;
  z-index: 2;
  font: normal 8pt sans-serif;
  padding: 3px;
  border: solid 1px rgb(0, 0, 255);
  color: white;
  background-repeat: repeat;
  background-image: url('debug_hint_bkg.png');
  }