[@mdawaffe Member 18 years, 4 months ago]

If you look at the default topic template (bb-templates/topic.php), you will see

<li id="post-<?php post_id(); ?>"<?php alt_class('post', $del_class); ?>>

the alt_class() function gives every other li element a class="alt".

So if you use that function in your topic template, you can put something like

.alt { background-color: red }

in your CSS file.