Multiple developers coding in the css file at the same time?

Hi everyone,

I have been researching how to use version control with wordpress. There is so much different information, plugins, etc.. that I am not sure where to start.
I am working in a newly start up small company of 3 persons. We mainly need to be able to be in the css or functions.php file at the same time without overwriting each other codes. Right now we have to wait until someone is finished before we can get into one of the files (we rarely use the functions file, mostly the css file).

Is there any version control or plugin that can help us with this?

Thank you