User Controls can have their own CSS stylesheets, which can get added to the Page's <HEAD> element when the control is loaded. In order to do this, the following needs to be done.
1. Add the RUNAT attribute to the page's HEAD element.
<head runat="server">
2. Make sure that the HEAD element does not contain any <% %> or <%= %> tags. This method will not work, if the head contains these tags.
3. Create a CSS stylesheet file.
4. In the Page_Load event, add the following code.