RubyMine 6.0 Stylus troubles

I created a new Rails 4.0.1 app in RubyMine 6.0, and added stylus to my Gemfile. I have the latest nodejs installed. I created a file in /app/stylesheets/foo.css.styl. But the styles defined in this file do not affect my markup. Sass files still work fine.

Also, I'm getting messages like this in the console:

Started GET "/stylesheets/foo.css.styl.css" for 127.0.0.1 at 2013-11-26 17:11:02 -0800

ActionController::RoutingError (No route matches [GET] "/stylesheets/foo.css.styl.css"):

Any suggestions?