[Lazarus] Howto disable Lazarus IDE using a XFCE dark theme

[Landmesser John]

New Linux Distro Manjaro-XFCE and i use a dark theme.

But that dark theme is bad for Lazarus IDE.

Can i change that as an option for compiling the IDE?

With Debian KDE there was in KDE Settings an option to prevent gtk-Apps 
using color-settings.

Perhaps an option in XFCE-Settings?

I'll keep on googling ...

Tipps are welcome!