<!DOCTYPE html>
<p>There should be a blue <em>square</em> below.</p>
<div style="-webkit-columns:2; -webkit-column-gap:0; width:100px;">
    <div id="container">
        <div style="-webkit-column-span:all;"></div>
        <div style="position:absolute; top:0; left:0; width:50px; height:200px; background:blue;"></div>
    </div>
</div>
<script>
    document.body.offsetTop;
    document.getElementById("container").style.position = "relative";
</script>