Structure Of ASP.Net Site

OK quick question and I assume the answer will boil down to preference.

Most developers tend to have a location for there .Net controls and master pages /Includes/Master etc and the same for cc/js/flash /assets/js etc etc

However, when developing a secure section (Assume /Admin) of the site do you add the css/masters to the same folders as the rest of the site or do you add new folders to the /Admin directory so your css would be in /Admin/Assets/Css/ etc

Thoughts and opinions welcome.

Pino