How to organize CSS code in the Full Code Editor?

I prefer writing CSS code manually. For larger projects, I am looking for a way to better organize my code.

In the Single Selector Code Editor, there are folders for that purpose. I know that I can write CSS code manually here as well, but this is limited and risky, since Microthemer processes my input in various ways, which I don’t want (e.g. comments and blank lines are removed; the first selector is renamed in certain situations).

I would love to have the possibility to create multiple stylesheets in the Full Code Editor, just to make it easier to organize and navigate my code.

Or are there any other options that I am missing?