When the list is shown in the side-pane, the background of the currently-selected discussion is the @control-bg. The hover color shouldn't be quite as strong as that.
- Get rid of Bootstrap (except we still rely on some JS)
- Use BEM class names
- Rework variables/theme config
- Fix various bugs, including some on mobile
The CSS is still not ideal – it needs to be cleaned up some more. But
that can be a focus for after beta.