Rework some CSS with new Scrollbar in Conpherence

Summary: Cleans up spacing, missed rules, double scrollbars, and make mobile pretty. Still need to re-work mobile submit.

Test Plan: Review Conpherence on Mobile, Tablet, and Desktop.

Reviewers: epriestley, btrahan

Reviewed By: btrahan

Subscribers: Korvin, epriestley

Differential Revision: https://secure.phabricator.com/D12414