<div>
  <ul>
    <li><a href="#"><img src="http://placehold.it/150x150"></a></li>
    <li><a href="#"><img src="http://placehold.it/150x150"></a></li>
    <li><a href="#"><img src="http://placehold.it/150x150"></a></li>
    <li><a href="#"><img src="http://placehold.it/150x150"></a></li>
    <li><a href="#"><img src="http://placehold.it/150x150"></a></li>
    <li><a href="#"><img src="http://placehold.it/150x150"></a></li>
    <li><a href="#"><img src="http://placehold.it/150x150"></a></li>
    <li><a href="#"><img src="http://placehold.it/150x150"></a></li>
    <li><a href="#"><img src="http://placehold.it/150x150"></a></li>
    <li><a href="#"><img src="http://placehold.it/150x150"></a></li>
    <li><a href="#"><img src="http://placehold.it/150x150"></a></li>
    <li><a href="#"><img src="http://placehold.it/150x150"></a></li>
    <li><a href="#"><img src="http://placehold.it/150x150"></a></li>
    <li><a href="#"><img src="http://placehold.it/150x150"></a></li>
    <li><a href="#"><img src="http://placehold.it/150x150"></a></li>
  </ul>
</div>
* {
  margin: 0;
  padding: 0;
}
 
body {
  background: #333;
}
 
div {
  width: 900px;
  margin: 0 auto;
  overflow: auto;
}
 
ul {
  list-style-type: none;
}
 
li img {
  float: left;
  margin: 10px;
  border: 5px solid #fff;
 
  -webkit-transition: box-shadow 0.5s ease;
  -moz-transition: box-shadow 0.5s ease;
  -o-transition: box-shadow 0.5s ease;
  -ms-transition: box-shadow 0.5s ease;
  transition: box-shadow 0.5s ease;
}
 
li img:hover {
  -webkit-box-shadow: 0px 0px 7px rgba(255,255,255,0.9);
  box-shadow: 0px 0px 7px rgba(255,255,255,0.9);
}

External CSS

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External JavaScript

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