Ajax with css content as data

Ajax with css content as data

When I post a simple data with ajax to the server it works fine.
Now I need to post some css content and I want the Php code in the server to create and write this code into the created file.
So actually I need help on both sides: How to post and how to treat it in the Php.
Can someone direct me how to do it?
Regards
I. lesher