title: Bootstrap. How to add multiple add affix attribute?
body: <p>I'm using Bootstrap Affix like this :</p>
  
  <pre><code>&lt;div data-spy="affix" data-offset-top="220"&gt;
  </code></pre>
  
  <p>And i add this css for fix the position when affix is triggered : </p>
  
  <pre><code>.affix {
          position: fixed; 
          top: 20px; 
          z-index:1;
          margin-left: auto ; 
          margin-right: auto ;
      }
  </code></pre>
  
  <p>Is it possible to use the Affix on several Dom element and affect a different css, something like this :</p>
  
  <pre><code>&lt;div data-spy="affix2" data-offset-top="220"&gt;
  .affix2 {
              position: fixed; 
              top: 50px; 
              z-index:1;
          }
  </code></pre>