The Styleboost plugin provides your Alchemy application and plugins access to several popular front-end frameworks.
You can use the stylesheet files by importing it like you normally would, for example:
@import 'bootstrap/bootstrap';
The bootstrap files can be overloaded in your base app or plugin folder by
simply creating an assets/stylesheets/bootstrap/filetooverload.less
file.
This overloading won't necesarily affect plugins, as they're encouraged to use the original, un-overloadable files using the following import:
@import 'original/bootstrap/bootstrap';
This does not mean you can't overload plugin styles, it means you'll have to overload the plugin's less files themselves.