Why are you forcing a Dark Theme?

I have been using this product for years, and with a new install there is no option for a light theme. I tried to force a light theme using GTK_THEME=Adwaita:light flowblade having no luck. I have a hard time seeing in all black, I love this app, so please add a option for the light/dark user choice for theme. I cannot use your app now, and I use it all of the time, but now i cannot use your app due to the dark theme only. Having a dark theme strains my eyes and I know it does for others as well, please if you could add this option in the pref's that would be appreciated very much, and thank you for all the hard work you have put into this app. Thank you again for taking the time to read this!