[Demo16]

Lynne tnx for the reply, I've already tried that but the html code is with div connected to css style. For example:

<div id="bd">
<div class="yui-g" style="width:360px;">
<div class="yui-u yui-panel">
<ul class="list_no_decoration" id="widgetlist_column2">$column[2]</ul>
</div>

in red what I've customized. But it doesn't work anyway.
The problem is that divs you can see when you flat the grid use a CSS class stored on a stylesheet, for this reason you must go and edit also the stylesheet It can be done but if there's an update of the board maybe you'll screw up everything. For this reason I am asking if there's an "official" way to do it.