Add field "RTMaterial" for project.
You can selected color for RTMaterial Theme (https://github.com/fraoustin/RTMaterial) by project Or you can selected color default for RTMaterial Theme (https://github.com/fraoustin/RTMaterial) by project.
$ cd redmine/plugins
$ git clone https://github.com/fraoustin/redmine_rtmaterial.git
$ rake redmine:plugins:migrate NAME=redmine_rtmaterial
restart Redmine
for uninstall, you can use
$ cd redmine/plugins
$ rake redmine:plugins:migrate NAME=redmine_rtmaterial VERSION=0
restart Redmine