An openbox theme will define the look of the window (the border, the title bar) and the right click menu.
To install a theme, copy it to a specific theme folder, then use obconf to apply.
I will illustrate with an Openbox theme called Mistral.
The author has posted it here:
In this case, the theme is packed in a folder. Openbox themes also come with .obt extension and can be installed using Obconf (You can extract that .obt package to a folder using any compression tool).
After having the theme folder, move it into one of theme directories below:
- System-wide themes are installed in: /usr/share/themes.
- User-specific themes are in: ~/.local/share/themes or in ~/.themes.
The theme will be instantly registered into Obconf.
Select Mistral theme.