Zi

is a CSS post-processor.

is the important bit: it returns a json object that looks a lot like normal css. replace this method with your own.

injects a synthetic style tag into the head of the html document, if it's not there, and injects the css.

just transforms the results of the zi.config method into a string appropriate to injection into that style tag.

Why do this?

because I'm a contrarian
because i would rather not keep track of both a CSS and JS file for every iteration of my app
because sometimes i need to do a calculation for styles based on the client and i don't want $.css junk all over the place
because once upon a time i needed the entire css/html base of an app as a single long string