<div style="position:relative; -webkit-column-count:2; -webkit-column-width:200px; -webkit-column-gap:20px; -webkit-column-fill:auto; column-count:2; column-width:200px; column-gap:20px; column-fill:auto; width:420px; height:200px; border:2px solid black;">
<div style="opacity:0.5">
<div style="height:400px;background-color:green"></div>
<div style="position:fixed;height:98px;width:98px;background-color:lightgray; left:170px; top:220px;background-color:green;border:1px solid lime">
</div>
</div>
</div>
</div>