<!DOCTYPE html>
<html>
<head>
<style>
  .scene {
    transform-style: preserve-3d;
  }
  .hidden {
    backface-visibility: hidden;
  }
  #inner {
    width: 20px;
    height: 20px;
    box-shadow: rgb(255, 205, 31) 0px 0px 0px 3px;
  }
</style>
</head>
<body>
<div class="scene">
    <div class="hidden">
        <div id="inner">
        </div>
    </div>
</div
</body>