Hi

I use KDE because of the applications and of the controls between applications and integration, not because of the attractive appearance, and often outside in the nature.

As developers prefer actually present the pretty look of the plasma 5 they use very dark environments, and, outside, I see nothing more...

I would need better in my Debian SID a light colored KDE with high contrasts...

I did loose a lot of time trying to download and change my KDE. Nothing to do probably because I don't understand which settings change what where!

In the past high contrast environments where available for laptop used outside and if I remember well, the settings were minimal to reach the right goal.

What is the actual solution?

Systemsettings > Applications Look > Colors, then select a nearest theme (e.g. Zion), then "Edit Colors..." and adjust to your likings.