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HTML

            
              .box
            
          
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↑ Insert the most common viewport meta tag

CSS

            
              .box {
  background-image: url("http://upload.wikimedia.org/wikipedia/commons/a/a8/Windows_XP_BSOD.png");
  background-size: 2px 2px;
  position: absolute;
  height: 60%;
  width: 60%;
  left: 20%;
  top: 20%;
}
            
          
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JS

            
              
            
          
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