feature(css): coding conventions based on medium.com's styleguide

> Medium uses a strict subset of LESS for style generation. This subset includes variables and mixins, but nothing else (no nesting, etc.).

> Medium's naming conventions are adapted from the work being done in the SUIT CSS framework. Which is to say, it relies on structured class names and meaningful hyphens (i.e., not using hyphens merely to separate words). This is to help work around the current limits of applying CSS to the DOM (i.e., the lack of style encapsulation) and to better communicate the relationships between classes.


Adding @fakewaffle @openam for discussion.