You should see the number 0 below, and the grey box should fit it snugly.

<span style="position:relative">
<div style="position:absolute;left:10px;top:10px;background-color:grey">
<div style="background-color:#acacac; padding:1px;">
    <div><div>0</div></div>
    <div id="one">1</div>
</div>
<script>
document.body.offsetLeft;
document.getElementById('one').style.display = 'none';
</script>
</span>