:active pseudo-class via php

[V]

I'm trying to create the active pseudo-class for selected links within <li> tags but it's not working. I'm not sure what I'm doing wrong.

 

Here's a sample code for one list item.

 

<ul class="sort">
<li <?php if ($sort == "most_popular") {print $selected;}  ?>>
<a href="categories.php?cat=<?php echo urlencode($cat); ?>&sort=most_popular">Most Viewed</a></li>
....
</ul>

 

When something is selected it does pick up the $selected variable which is class="active" but not the CSS:

 

.sort li:active {
background:#dddddd;
}

.sort li a:active {
color:#EB8F00;
}

 

any ideas?  :-\