navbar tab size

[gamaken]

I have created a new dropdown menu on my navbar. I would like to make the tab smaller than the other tabs. Basically I just want a small tab with the arrow graphic.

<li class="popupmenu">
<a href="javascript://" class="popupctrl navtab" style="background:transparent url({vb:stylevar imgdir_misc}/arrow.png) no-repeat {vb:stylevar right} center; padding-right: 15px"></a>
<ul class="popupbody popuphover">
<li><a style="color:{vb:stylevar navbar_selected_popup_body_a_Color}" href="search.php{vb:raw session.sessionurl_q}" accesskey="4">{vb:rawphrase advanced_search}</a></li>
</ul>
</li>

Is there a way to override the default width without changing the class? Thanks.