Brought over styles from Thinkup.com for main user, Facebook, and Twitter settings

Okay! We've agreed to move these into extras/dev/assets/src/, and add documentation so devs can update these properly. In the "Write code" section here https://www.thinkup.com/docs/contribute/developers/writecode/index.html let's add a page about modifying CSS and JS with LESS and CoffeeScript.