Make site more mobile-friendly

[Simran-B]

adityamukho in Community Slack:
the site doesn't appear to be too mobile friendly

1. topnav: other "books" not shown
2. hamburger button only reachable if content on the right-hand side is scrolled up to the top
3. clicking on the << previous / next >> links at the bottom re-opens the sidebar if it was closed

[Simran-B]

1 and 3 should be fixed meanwhile (there can be caching issues, use incognito window). Re 2 still waiting on decision for porting the website header, which would change the entire design including the hamburger button.

4. Orientation changes do not trigger some media query rules
   

5. Closing the sidebar also transitions the topnav elements (Manual, AQL, ...)

[Simran-B]

• If there's too little space for a headline next to the ToC, it should get pushed below the ToC.

• A code block at the top may flow under the ToC and make the links therein unclickable

• Tables are 100% wide, but if they are at the top they start below the ToC even though they could adjust

• Embedded YouTube player assumes a certain width, making videos be partially off-screen