[GNC] Moving from Windows to Linux

[AC]

I've been using Gnucash on my Windows machine for a while but I'm 
transitioning to a Linux machine as the daily driver. I need a few 
reminders for files to transfer and locations where to put them to make 
sure that the two look and behave the same way.

Obviously the first is the .gnucash data file which I already have moved 
and tested to make sure it at least opens with data, no issues there.

What file stores things like the account color (if one exists)? I opened 
the data file on the Linux side but none of the accounts had their 
assigned colors. If there is such a file, where does it end up on the 
Linux side?

Also, I customized the appearance of the UI (changing register colors, 
etc.) inside the gtk-3.0.css file. Where would these customizations go 
on the Linux side? I think I saw they go in USER_CONFIG_HOME?