How to reuse the Jahia web site CSS from a webapp deployed into it...

Hi,

I have a web site under Jahia with a web_css.jsp style sheet. I'm wondering
if it's possible web application deployed into:

 JAHIA_HOME/tomcat/webapps/jahia/WEB-INF/new_webapps/MY_SITE_NAME

has the hability to reuse the web<-css.jsp from tho jahia web site?

if so, what is the source code of line to write into my JSP? (What is the
correct path...)

Thanks.
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