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Stylesheet Coding Image Desaturation Effect 

.box img{
 filter: url("data:image/svg+xml;utf8,<svg xmlns=\'http://www.w3.org/2000/svg\'>
  <filter id=\'grayscale\'>
   <feColorMatrix type=\'saturate\' values=\'0.5\'/>
  </filter>
 </svg>#grayscale");
 filter: gray alpha(opacity=50);
 -webkit-filter: grayscale(50%);
 -webkit-transform: translateZ(0);
}
.box img:hover{
 filter: url("data:image/svg+xml;utf8,<svg xmlns=\'http://www.w3.org/2000/svg\'>
  <filter id=\'grayscale\'>
   <feColorMatrix type=\'saturate\' values=\'1\'/>
  </filter>
 </svg>#grayscale");
 -webkit-filter: grayscale(0%);
}