I think this will do what you want.
At top of the three pages:
<cfset noShow=1>
Change the css sheet to a .cfm script and use <cfinclude>.
Inside the css sheet:
<cfparam name="noShow" default="0">
<cffif not noShow>
....... Bar elements here .......
</cfif>
Without making the css sheet into a dynamic document, I'm not sure you can really do this since any regular style sheets are downloaded after the browser receives the completed output from CF.
Hope this helps,
GJ