omputedStyle(target).columnGap, "normal");
      }, "Negative column-gap is invalid");
    test(
      function(){
        var target = document.getElementById("invalidColumnGapMaxContent");
        assert_equals(getComputedStyle(target).columnGap, "normal");
      }, "'max-content' column-gap is invalid");
    test(
      function(){
        var target = document.getElementById("invalidColumnGapNone");
        assert_equals(getComputedStyle(target).columnGap, "normal");
      }, "'none' column-gap is inval