header of rhtml template

Hi, I wrote an rhtml view to generate the css stylesheet file for the web page. The url that I can generate is correct: http://127.0.0.1:3000/stylesheets/99/style_software/r-firewall.css

But the r-firewall.css file properties are file type text/html because in default all the view.rhtml generate text/html file.

Someone can tell me how I can change the file header and so the file type in text/css of a view.rhtml?

Thank you.

Luigi