Update Landing Page Header/Menu

[CSchmitz81]

Update the landing page header bar (desktop) and menu (mobile) to match the comps. For desktop this means removing the tabs and just showing links. The link for the current page should be highlighted in green (as shown for the "Overview" link in the comp). If there's not enough room to show the "Collaboration Tree" label and links on the same row, they should be split into separate rows.

For the mobile, update the top bar style to match the comps. There's no comp showing the menu, it should be updated so the style is consistent with the updated site.

If possible, hide the top bar when the user scrolls down and reveal it when the user starts scrolling back up, for both desktop and mobile. If that's not possible, keep the top bar in place at all times.

Please base your changes on the develop-landing-page branch.

[CSchmitz81]

Hey @KyleHefner, I just wanted to check in to see if you've made any progress on this. I haven't seen any responses on the PR (#126) for the past couple months, so I wanted to see if I should free this up for someone else to work on.

[CSchmitz81]

Progress has stalled on PR #126. Went ahead and merged it so the partial implementation can be included. Additional work should pick up from where #126 left off, taking into consideration the comments from #126.

[CSchmitz81]

Reverted merging #126 because it caused regressions in the layout. The branch was restored, so work should continue in that branch (develop-landing-page-landing-page-header-#121), including resolving these regressions.