I am developing a native app with Expo for the first time. I am using their Expo-router and tabs.

I am getting a base background of gray color in the whole app from Expo, probably rgb(242,242,242) in light mode and rgb(1,1,1) in dark mode. It seems to be some kind of "standard colors" from Expo with unknown adress. I can not find a way to change "this" color.

I have tried to search the project, google and I have asked AI. But I can not find an answer that changes this background color.

Below are my screenshots from iOS simulator with light and dark mode.