title: I'm having validation problems (w3 validator, html5) when using FancyBox JavaScript when using rel attribute
body: <p>I'm having the validation problems (w3 validator, html5) when using FancyBox JavaScript </p>
  
  <p>" Bad value group for attribute rel on element a: Not an absolute IRI. The string group is not a registered keyword or absolute URL. "</p>
  
  <p>This is the code:</p>
  
  <pre><code>&lt;a class="fancybox" rel="group" href="1-big.jpg"&gt;&lt;img class ="fbox" src="1-small.jpg" alt="slideshow" /&gt;&lt;/a&gt;
  &lt;a class="fancybox" rel="group" href="2-big.jpg"&gt;&lt;img class ="fbox" src="2-small.jpg" alt="slideshow" /&gt;&lt;/a&gt;
  &lt;a class="fancybox" rel="group" href="3-big.jpg"&gt;&lt;img class ="fbox" src="3-small.jpg" alt="slideshow" /&gt;&lt;/a&gt;
  &lt;a class="fancybox" rel="group" href="4-big.jpg"&gt;&lt;img class ="fbox" src="4-small.jpg" alt="slideshow" /&gt;&lt;/a&gt;
  &lt;a class="fancybox" rel="group" href="5-big.jpg"&gt;&lt;img class ="fbox" src="5-small.jpg" alt="slideshow" /&gt;&lt;/a&gt;
  &lt;a class="fancybox" rel="group" href="6-big.jpg"&gt;&lt;img class ="fbox" src="6-small.jpg" alt="slideshow" /&gt;&lt;/a&gt;
  </code></pre>
  
  <p>I tried the using the data attribute instead of rel to no avail.</p>
  
  <p>If I change it to class then I get the error of having 2 classes in the same a tag, I'm new to html as this is my first year at uni, I was wondering if anyone has a valid substitute/solutions.</p>