t>
    test(
      function(){
        var target = document.getElementById("default");
        assert_equals(getComputedStyle(target).columnGap, "normal");
      }, "Default column-gap is 'normal'");
    test(
      function(){
        var target = document.getElementById("columnGapPx");
        assert_equals(getComputedStyle(target).columnGap, "12px");
      }, "column-gap accepts pixels");
    test(
      function(){
        var target = document.getElementById("columnGapEm");
        assert_equals(getCo