So, here is the css and python script used to create it. I've did only country part of css, but I guess it would be easy to use it. I also had error in previous archive - USA file has extra quote at the end, it must be 'Murica, not 'Murica'.

(both files need to be stripped from .txt extesion because endchan doesn't allow to uploading these files in original form)

CSS is made by script, but I guess some images need update, and this script helps to generate css after these updates.

Usage:
python balls.py --dir /path/to/balls/directory --css /path/to/custom.css
(--css is optional)

What does it do:
1) If css is supplied, it tries to download images from imgur that missing from balls directory. I.e. you have dir/Hungary.png and dir/Vatican.png, but css contains ball for Venezuela, so that ball will be downloaded as dir/Venezuela.png. Name for ball is taken from css rule "title" param.

2) It goes over images in dir, gets their content in base64, dimensions, format and name.

3) It generates css using data from 2, sorted alphabetically.