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HTML

            
              <img src="http://i.imgur.com/3gFA7PD.jpg" />
            
          
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↑ Insert the most common viewport meta tag

CSS

            
              	@shadow-blur:			8px;		

	.outer-shadow(@alpha: 0.3) {
  		-webkit-box-shadow: 0 0 @shadow-blur rgba(0, 0, 0, @alpha);
  		-moz-box-shadow: 0 0 @shadow-blur rgba(0, 0, 0, @alpha);
 		 box-shadow: 0 0 @shadow-blur rgba(0, 0, 0, @alpha);
		}

img {.outer-shadow(.5)}
img:hover {.outer-shadow(1)}
            
          
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JS

            
              
            
          
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