<html>
<head>
<script>
function test()
{
var div = document.createElement("div");
document.body.appendChild(div);
document.body.removeChild(document.body.lastChild);
}
</script>
</head>
<body onload="test()">
<div style="display: inline-block; width: 100px; height: 100px; background: red;">
<div style="width: 100px; height: 100px; background: green; opacity: 0.9;">
</div>
</div>
</body>
</html>