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 <h1>Highlighting images lacking an alt tag</h1>
  <p>This can be tested using just a bit of css. I wouldn't make this a permanent part of my stylesheet, but it could be added to the bottom of the style sheet before a project is launched just to see if all of my images have alt tags.</p>
  <p>To do this, the style sheet will create a black border around all images with an alt tag present. Next, it will create a red border around any images that don't have an alt tag. The css code to do this is:</p>
  <pre>img[alt] {border: solid 5px black;}
img {border:solid 5px red;}</pre>
   <h2>This is an image with an alt tag:</h2>
  <p>It should have a black border that is 5px thick.</p>
  <img src="" alt="image with alt tag" />
  <hr />
  <h2>This is an image without an alt tag:</h2>
  <p>It should have a red border that is 5px thick.</p>
    <img src="" />


                h2 {clear:both; color:blue;}

img {border:solid 5px red;}
img[alt] {border: solid 5px black;}