Searching with keywords

[garrett]

I still can't push to your branch (or even see it in the PR dropdowns unless I manually mess with the URL), so here's a PR to your PR that

• fixes search sizing
• removes top nav fade
• restructures the search class to only apply when inside the nav (as "search" is quite generic... and we might want to think of another name for the class overall, like ct-nav-search)