This can happen if you have a syntax error in module.css

Do you see module.css in the list of loaded css files in the page source?

Do you see the module.css  classes overridden in firebug?

Did you try removing everything from module.css  and put only one simple class and see if it works?

Otherwise more info is needed.

After looking at the DNN rendered page I can see that module.css is being called.  Module.css looks like this:

.gridHover {     background-color: #a51b01;     color: White;     cursor: default;        } .gridOut {     background-color: White;     color: #a51b01;    }

It id not working on my rended table (in source its a gridview)... the code for the table and a row looks like this *http://hayesvillefreewill.org.dnnmax.com/Sermons.aspx):

  <table  cellspacing="0" rules="all" border="1" id="dnn_ctr408_Sermon_List_dgvSermon"   style="font-family:Lucida Console;font-size:8pt;width:100%;border-collapse:collapse;">        <tr class="gridOut" onmouseover="this.className = 'gridHover'"   onmouseout="this.className = 'gridOut'" onclick="location.href=genQueryString(620);">      <td style="width:100px;">Sun 03/28 AMtd><td style="width:100px;">Chris Rumfelttd> <td>Three Men &amp; Their Stormtd>tr>
    <tr class="gridOut" onmouseover="this.className = 'gridHover'"  onmouseout="this.className = 'gridOut'" onclick="location.href=genQueryString(619);">
    <td>Wed 03/24 PMtd><td>Chris Rumfelttd><td>Thy Rodtd>tr>
    <tr class="gridOut" onmouseover="this.className = 'gridHover'"  onmouseout="this.className = 'gridOut'" onclick="location.href=genQueryString(618);">  
  <td>Sun 03/21 PMtd><td>Randy Hoopertd><td>There's More to it Than Thistd>tr> ....

If you goto http://hayesvillefreewill.org.dnnmax.com/Sermons.aspx you can see that the table when not hightlighted has white background with black foreground.  This is supposed to be white back red front.  When you hover over a row the background turns red but the forground is some blue not white....

Not sure what I am doing wrong, I specifically told it what I wanted on the class style of the row.  I have dont this before out of DNN and worked great, obviously even though I am giving it a class to look at it is still be overrided by some other CSS file somewhere.