<!DOCTYPE HTML>
<html>
<body>
<div style="opacity:0.8; background-color: gray;">
  <span style="display:inline-block; width:256px; height:256px; background:lime; position:relative; top:10px;">
    <div style="background:yellow; height:50px;"></div>
  </span>
</div>
</body>
</html>