<script>
internals.settings.setCSSVariablesEnabled(true);
</script>
<style>
body {
    -webkit-var-a: bold;
    font-weight: normal;
    font-weight: -webkit-var(a);
}
</style>
<body>
Test failed - JS did not run
</body>
<script>
var element = document.body;
var weight = window.getComputedStyle(element, null).getPropertyValue("font-weight");
if (weight == "bold")
  element.innerHTML = "Test passed - computed font weight is bold";
else
  element.innerHTML = "Test failed - computed color is " + weight;
</script>