Linguist hardcoded background colors when working with >1 language

Qt Linguist uses hardcoded, or maybe calculated background colors for the main translation area of its interface, when working with more than two target languages. The point, apparently, is showing each target language with a different background, to make the difference more obvious.

The problem appears when the user is not using a typical "lightgray/white backgrounds with black text" color schemes. If you use a darkish color theme, then your system color for text will probably be white or something quite bright, and you'll expect darkish backgrounds.

In this case, the calculated shades for the background colors are bright, which in this kind of configuration, makes that part of the UI unreadable.

Interestingly, when working with just one target language, there's no calculated/hardcoded color, so everything is fine, using the system color scheme.

Check attached screenshots for a sample of each case.

Thanks!