OneStepBack is a Gtk 2, 3 and 4 theme with some colors and embossed widgets inspired by the good old NeXTSTEP look. It is developed from scratch, is light and minimal, uses only three shades of grays and one color.<p>It has been tested on Arch Linux with Gnome-Shell, Gtk+ from 3.16 to 3.24 and Gtk+ 4.12.4, a good amount of Gtk2 and Gtk3 applications and a very few Gtk4 applications. A lot of widget controls are still missing (but the defaults should be good enough) and it is not tested at all with unity or xfce.<p>QT applications can use some base colors of the gtk theme after installing qt5-styleplugins and qt6gtk2, for a more consistent overall appearance.