      https://www.w3.org/TR/css-backgrounds-3/#border-image-repeat
      "
      */
      border-image-slice: 64 fill; /* the center will be black */
      border-image-source: url("support/4bicolor-squares.png");
      display: inline-block;
      image-rendering: pixelated; /* attempt to overcome antialias fuzziness */
      margin-right: 1em;
      vertical-align: bottom;
   }

  div#first-subtest
    {
      height: 96px;
      width: 96px;
      /*
      96px divided by 64px == 1.5 which is rounded up 