Css highlighting in php

I’m currently working on a php heavy web project. After changes were made to Css files, they were not loaded correctly. To prevent that, I now use php files with Css header instead. Now I am looking for a way to highlight Css syntax correctly in a Php file to make editing easier. Does anyone have an idea how?
Thanks in advance.

I would just keep css in separate files and php include them into php main files. Then you can edit external css files, or snippets, separately using say Beautify.

thx i will try that as soon im back in at the projekt.