You have closed each list item in the submenu before the ul for the sub-submenu.
html should look like this fiddle:
<ul>
<li>Home</li>
<li>Bio</li>
<li>Portfolio
<ul>
<li>Design
<ul>
<li>Illustartor</li>
<li>InDesign</li>
<li>Photoshop</li>
</ul>
</li>
<li>Media
<ul>
<li>Photography</li>
<li>Video</li>
</ul>
</li>
<li>Traditional
<ul>
<li>Paintings</li>
<li>Drawings</li>
</ul>
</li>
</ul>
</li>
<li>FAQ</li>
<li>Contact</li>
</ul>
I have changed some of the css in the fiddle as well utilizing direct descendent selectors. Inheritance is very important here. when you style ul li {
that will cascade down to ul li ul li {
as you are styling all li
that are children of a ul
. doesn't matter how many levels deep.