Modification of Numix Theme taken from Debian Stretch Repo. Intended for personal use but posted here as a reference to my r/unixporn post.
Intended for use with Openbox, has not been tested with any other WMs, modifications are primarily to the gtk3.20 dark theme, with some modifications to the light theme for the sake of Firefox. Zero modification to gtk2 themes as the number of gtk2 applications rapidly approaches zero.