Tried to design a dark theme based on my store's emergency exit signs. Big mistake.

I was making a dark mode for a hobby app and thought the green on black from exit signs would work great. So I set the background to pure black and the text to that bright emergency green. After using it for a bit, my eyes started to ache and everything looked weirdly intense. It was like the app was shouting at me in a dark room, which is the opposite of what dark mode should do. I'm really confused why some designers pick colors that seem clear but end up hurting your eyes. Is there a trick to picking colors that are easy to read without being too harsh? Now I'm rethinking the whole color palette from scratch.