.htaccess RewriteRule question

[HowlingWulf]

I have a script that uses an arg to grab a picture in the form
http://www.mydomain.com/?picid=10

I'd like to use .htaccess to be able to use
http://www.mydomain.com/pic10/

I have
RewriteRule ^pic(.+)/$ /?picid=$1
which sort of works in that it loads the script with the proper arg

however the problem is the script loads .css files and other images in a relative path, so I'm seeing this in the logs:
/pic10/images/something.jpg
instead of
/images/something.jpg

Is there a second Rewrite Rule I could use to fix this? I've tried
RewriteRule ^pic.+/(.+)$ /$1
but no luck.