Navbar: clearer separation between lang/theme selector and other links

[WorldLanguages]

I think it's weird that "community" is a list of links, meanwhile the language selector is not, yet they look the same and the margin is the same as all other pairs of links.

Maybe we can add a line and some margin between "community" and the language selector. What do you think?

[WorldLanguages]

Note that some pages don't have a language selector. But all have a theme button.

[Hans5958]

Hmm, separating it would be a good idea, but would be awkward if we add it when there is just one.

I was thinking separate in a radical way. I want to have a floating button, but again, it wouldn't look nice.

A better compromise is to put it on the footer, just like how the TypeScript Documentation (theme) and Scratch (language) does it.

[WorldLanguages]

Actually I like these buttons at the top.
Our website is usually visited from desktop (or, more generally, wide screens) and it has no login, so we should take advantage of the space!

[Hans5958]

We actually got an ideal amount of navbar links, not to crowded and not to bare, even if we remove the theme and language buttons, I think.

Also, the reason I put it to also support mobile is that to reach as many potential users, even though they would need to use their PCs to install it. Also, 8% is nice enough to reach, even if we don't prioritze it that much.