ASP 2.0 Menu Navigation Implementation

[tennisguywill]

I am using MS Expression Web and I understand the basics of adding a vertical menu. My problem is after inserting the ASP menu control and linking it to the web.sitemap file; how do I link my menu1.css file that contains the CSS to format my menu? I inserted the CSS directly into the master page and the style does not show up in the menu. Do I need to create a web.config file? If so, can you please explain in beginner language how to do that? Also, does having multiple web.sitemap files present a problem? Can they be named (whatever).sitemap? Thanks in advance for any help provided.