When I use the 23 column layout to display the items in a category the 3rd column does not show because each column is too wide. div.itemContainer is set to 33.3%. If I change it ( in firebug) to 28% it works fine but I do not know where to make the change. The css code, with no identification of what file it is in, shows:

element.style {width: 33.3%;}

The html looks like:
<div class="itemList">
<div id="itemListPrimary">
<div class="itemContainer" style="width:33.3%;">
<div class="itemContainer" style="width:33.3%;">
<div class="itemContainer itemContainerLast" style="width:33.3%;">
<div class="clr"></div>
<div class="itemContainer" style="width:33.3%;">
<div class="itemContainer" style="width:33.3%;">
<div class="itemContainer itemContainerLast" style="width:33.3%;">
<div class="clr"></div>
<div class="itemContainer" style="width:33.3%;">
<div class="itemContainer" style="width:33.3%;">
<div class="clr"></div>
</div>
</div>