Here is a new Openbox theme, which will be the default in PostX Gnu/Linux 0.5.
E221 uses dark colours but remains easy on the eyes. Highlighting colours are yellow for the buttons and blue for the menu and osd. Close, maximize and minimize buttons are custom-made. Below, a screenshot and the theme archive.
#Openbox theme E221 Copyright 2017 by JJ Posti from techtimejourney.net. Theme is GPL