You can create your own theme layout by placing a file in:
${HOME}/.config/sbp/themes/colors/${your_color_theme_name}.bash
Theme colors are basically 16 RGB values. And I've added a template
template.ejs that can be used with Base16 Builder to generate a colors
file from your favorite color scheme. For instance like so:
base16-builder --scheme 3024 --template themes/template.ejs --brightness dark > themes/colors/3024.bash
You can also set the colors to be xresources which will use whatever theme is
set in your terminal/xresources config.