How do I change an attribute of an element when someone scroll pass the element (Sticky Element)
<p>For example <a href="http://twitter.github.com/bootstrap/base-css.html" rel="nofollow">http://twitter.github.com/bootstrap/base-css.html</a> try to scroll up. You will see the bar with </p>

<blockquote>
  <p>"Typography Code Tables Forms Buttons Icons by Glyphicons"</p>
</blockquote>

<p>when you scroll pass the element it will add a class to make the element change. While you are scrolling back up it will remove the attribute to change the element again.</p>

<p>Edit: I found out this is call Sticky Element.</p>
