SwiftUI - the bottom sheet has an area which changes the background on contact with content

What i want

There is a bottom sheet in the settings default app, in this bottom sheet there is a certain area with a button that changes the background when it comes into contact with content such as a NavigationBar or a TabView. How can this be implemented?

I tried putting a button in toolbar on the bottom bar, it worked fine and close to what I wanted, but the area is too small. I also tried .safeAreaInset with .bottomBar placement , but how to make the background change from what is above the content and disappear when there is no content below it like in video .