<!DOCTYPE html>
<html>
<style>
  #target {
    height:  100px;
    width:  100px;
    background:  green;
    display:  inline-block;
    margin:  10px;
  }
  #container {
    filter:  blur(5px);
  }
</style>
<body>
  <div id="container">
    <div id="target"></div>
  </div>
</body>
</html>
