How do you set the background color of a toolbar button in ios26?

I noticed the image playground button turns blue when it's ready. Nothing I do changes the background color. Is there a way to make that happen?

I tried to attach a screenshot but it wouldn't let me.

        ToolbarItem {
            Button {
                print("Button pressed")
            } label: {
                Image(systemName: "star")
            }
            .tint(.yellow)
            .buttonStyle(.glassProminent)
        }

This will result in:

How do you set the background color of a toolbar button in ios26?
 
 
Q