Thanks Mirek!

Looks very good now!

As to your question, now we can do this:

#include <CtrlLib/CtrlLib.h>

using namespace Upp;

struct MainWindow : public TopWindow{
	MenuBar menu;

	MainWindow() {
		Title("Dynamic Theming Sample").Sizeable();
		AddFrame(menu);
		menu.Set([=](Bar& bar) {
			bar.Sub("Theme",[=](Bar& bar) {
				bar.Add("Host platform (dynamic)",[=] { Ctrl::SkinChangeSensitive(true);  SetDarkThemeEnabled(true); Ctrl::SetSkin(ChHostSkin); });
				bar.Add("Host platform (forced dark)",[=] { Ctrl::SkinChangeSensitive(false);  SetDarkThemeEnabled(true); Ctrl::SetSkin(ChHostSkin); });
				bar.Add("Host platform (forced light)",[=] { Ctrl::SkinChangeSensitive(false);  SetDarkThemeEnabled(false); Ctrl::SetSkin(ChHostSkin); });
				bar.Add("Custom theme (static)",[=] { Ctrl::SkinChangeSensitive(false);  Ctrl::SetSkin(ChStdSkin); });
			});
		});
	}
	
};

GUI_APP_MAIN{
	Ctrl::SkinChangeSensitive(true);
	Ctrl::SetDarkThemeEnabled(true);

	MainWindow().Run();
}

This new automatic theme responsiveness added with manual control keeps maritime users happy: Many of them like to have the entire desktop with all apps dark at night and light during daytime. Night at sea is really dark and it requires dimming each and every light on the ship's bridge to its minimum to be able to see much anything ahead. (There's even a utility available for Windows that automatically switches between light and dark themes based on Sun rise and Sun set times.) But as always, some users wish to have it exactly their way with different themes on different applications. So, now everyone (excluding some even more difficult users) can have it their way.

Thanks and best regards,

Tom