You can simply change font colour and background colour using this Module.
It provides fully responsive mobile adminLTE Bootstrap for Backend Theme Odoo Community web
This module provides feature for changing layout of theme.
Blue Backend Theme V8
Bootswatch Darkly
Bootswatch Lumen
Bootswatch Paper
Bootswatch Sandstone
Bootswatch Superhero
Build Your Enterprise Website on one Bootstrap page
This module provides feature for carousel-thumbnail-indicators theme.