l.CssClass will have an effect if you put the class name from the style in it. For instance:
<style type="text/css">
.boldText {text-weight: bold}
</style>
// then the following should work
l.CssClass = "boldText";
// this will generate: <span class="boldText">your text</span>
If you just want to add a style directly, you can do the following:
l.Attributes.Add("style", "color:Red;font-weight:bold;");
, . !
PS:
<asp:Literal>
<asp:Label> <SPAN>
<asp:Panel> <DIV>
EDITED on 2010.12.09 -