I have decided to change theme in LXDE to Adwaita-dark. I noticed that GTK+ 3 apps are white and GTK+ 2 apps are dark. If I use default Adwaita theme, GTK+ 3 apps are dark and GTK+ 2 apps are white. Other themes doesn't have this problem. I tried to set manually dark theme in dconf, adding gtk-application-prefer-dark-theme=1 to settings.ini, but nothing helped. Can you help me, please?