CodePen

HTML

            
              <div>
  <img src="http://placekitten.com/300/200" alt="kitty">
</div>
            
          
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↑ Insert the most common viewport meta tag

CSS

            
              div { width: 550px; height: 250px; background: red; }

img { display: block; margin: 0 auto; }
            
          
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JS

            
              
            
          
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