Improve pop-up menu colors

[amarakon]

There are three areas in which I improved the pop-up menu colors:

1. The background color is darker but still not as dark as the terminal background color, making it easier to notice the selected item.
2. The foreground color for selected items remains unchanged because it is not needed to notice the selected item because of the above change.
3. Since the background color is now darker, you can actually notice the scrollbar on the right if it exists.

Before and After

It looks a lot better in my opinion.

[svengreb]

Thank you for your patience! 🙏🏼
It‘s been a while since I had free time to focus more on Nord, and my open source projects in general, and invest time in this issue due to work-life balance.

I recently published the first “Northern Post — The state and roadmap of Nord“ announcement which includes all details about the plans and future of the Nord project, including the goal of catching up with the backlog. This issue is part of the backlog and therefore I want to triage and process it to get one step closer to a “clean state“. Read the announcement about reaching the “clean“ contribution triage state in Nord‘s discussions for more details about the goal.

Therefore it has been added for triage in the central and single-source-of-truth project board that is also described in more detail in the roadmap announcement.

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@amarakon Thanks for your contribution 🚀
The pull request has been added for triage and the review will be planned for the next iterations!