Matter is a material design system built on top of the latest version of bootstrap. It's released under MIT which means you can do whatever you want with it, you can use it for your personal projects, client projects or you can sell it, there are no limitations.
Matter is a part of a failed side project. It was meant to help developers build applications more easily no matter the environment. Long story short, the maintainer (Alex Andonie) lost his interest in the project and everything fell apart. To pursue the initial idea of wanting to help other developers and to keep the project alive, Alex decided to refactor Matter and release it for free. The version you're currently viewing is a stripped down version. More components will be added as they get refactored. Star and watch the repo to get notified of the new additions and if you want to add, fix or change something, feel free to submit a PR as all the good stuff will get merged.Fork on Github