mputedStyle(target).columnGap, "20px");
      }, "column-gap accepts em");
    test(
      function(){
        var target = document.getElementById("columnGapVw");
        // The columnGap size would depend on the viewport width, so to make the test pass
        // in any window size we just check it's not "normal".
        assert_not_equals(getComputedStyle(target).columnGap, "normal");
      }, "column-gap accepts vw");
    test(
      function(){
        var target = document.getElementById("columnGapPer