<!DOCTYPE HTML>
<div style="width: 100px; height: 100px; opacity: 0.8; -webkit-box-shadow: 0px 0px 5px 5px #fff;">
  <div style="position: relative; z-index: -1; width: 10px; height: 10px; background: blue"></div>
  <div style="width: 40px; height: 40px; background: orange;"></div>
  <div style="width: 40px; height: 40px; background: green; transform: translateZ(0);"></div>
</div>