This comes from Genome Dark's colors. It is a slight adjustment to Breeze Dark. Malice is also included.
This color scheme is used in Spectrum Dark
Have you tried turning it off and on again? Sometimes plasma assets will not update and some may still be themed according to something you previously had set. This can usually be fixed by restarting.
To restart just plasmashell, open KRunner with "Alt + F2" to execute the following 2 lines: