presentation-angular-and-react
I also like the grep-ability of _cls in CSS, since you're linking two very widely removed pieces of code, and one potentially has almost global scope (it's really hard to understand the scoping of CSS, particularly when it's being compiled and included by SASS or the Asset Pipeline. What seems simple with a small codebase can becomes unmanagable with a larger one (for example, CSS classes called 'row').