Mobile display is broken on most pages

[ia3andy]

I recorded a few screenshots of display problems on the mobile website. IMO those issues are really bad and should be taken seriously and treated as urgently as possible. The mobile design really needs more attention.

Screen overflowing with a black background

Lines going outside of the screen

Tables displaying really badly

I also noticed a scroll bar in the middle of the screen on some guides.

CC @jkbrock

[FroMage]

Also the guides page's TOC is absent on mobile, which makes the page unusable, as we can't navigate it.