<body>
    <div style="background-color: red; width: 100px; height: 100px;">You should not see this. Resize the window.</div>
    <div id="target" style="position: absolute; left: 8; top: 108px;">
        <div style="position: absolute; left: 0; top: 0;">
            <div style="visibility: visible; width: 100px; height: 100px; background-color: green;"></div>
            <button>Button</button>
        </div>
    </div>
    <script>
        function test()
        {
            document.body.offsetTop;
            var t = document.getElementById("target");
            t.style.visibility = "hidden";
            t.style.top = "8";
        }
        test();
    </script>
</body>