Galaxy (https://galaxyproject.org) theme derived from bootstrap.
Example site served at http://jxtx.github.io/galaxy-bootstrap/
galaxy_bootstrap contains a variables.less that has been modified to remove almost all hardcoded colors. A small number of variables define primary color, border color, and how to derive other colors from them.
To build:
yarn run build
Which will build regular and minified css files into dist.
index.html is a sample stolen from Bootswatch that shows most things.