Sorry, I followed the instructions on that page, and I don't have a single file named "gtk.css", or any relevant "settings.ini"
You have to create them (at appropriate places). If I understand the stackoverflow page and the paths you describe correctly, you should copy the `Prof-gnome` directory from
https://github.com/geany/geany-osx
into
``` INSTALL_DIR\share\themes\ ```
(so there's `INSTALL_DIR\share\themes\Prof-Gnome...`)
The `settings.ini` file should look this way:
https://github.com/geany/geany-osx/blob/master/settings.ini
but without the `gtk-icon-theme-name` and `gtk-key-theme-name` lines and should go to ``` INSTALL_DIR\share\gtk-3.0\settings.ini ```