This is possible by adding some VB code to your ASCX skin.
Dim objTab As DotNetNuke.Entities.Tabs.TabInfo = CType(PortalSettings.ActiveTab.BreadCrumbs(0), DotNetNuke.Entities.Tabs.TabInfo)
will give you a TabInfo object from the breadcrumb (containing info for the page on level 0)
objTab.TabName will return the name of the Page on level 0.
if you wrap this in a function and return the page name:
<script runat="server">
function RootPageName () as string
Dim objTab As DotNetNuke.Entities.Tabs.TabInfo = CType(PortalSettings.ActiveTab.BreadCrumbs(0), DotNetNuke.Entities.Tabs.TabInfo)
Return objTab.TabName
end function
</script>
Now wrap your skin in a div:
<div class="<%=RootPageName%>">
"your skin"
</div>
<%=RootPageName%> will be replaced dynamically by the name of the breadcrumb page on level 0
I did not test the code, sorry for any typos, but you should get the idea.