Better dark-style unfocus dim

## Problem

The stylesheet currently dims and makes certain widgets paler, but not all. The widgets that do get dimmed are also not very obvious.

## Proposal

Consider a more stark contrast in the way that focused and unfocused widgets look:
- Consider dimming text very slightly, just about enough to notice (in general)
- Widgets in dark style should be much paler **or** should go in the other direction and get

Other things to consider:
- Consider whether unfocusing makes apps look dim or lack depth, maybe both (macOS Big Sur does this, but it isn't very helpful if the app is already flat)