A handy bag of Sass mixins and utilities, and the Sass little brother to Stylus's Axis Library.
Knapsack only provides pure css as defined by the w3c spec any browser prefixing can and should be applied by auto-prefixer.
Currently there are 3 installation options:
npm install knapsack
bower install knapsack
knapsack/indexinto your css pipeline
Full documentation is here.
Experiment with the latest version of Knapsack on Codepen.
gem install scss-lint
scss-lint knapsack -c .scss-style.yml
(Publishing instructions for contributors here)