showing ZStack with default alignment behavior

ZStackExample.swift

ZStack(alignment: .center) {
   Text("first item")
         .frame(width: 150, height: 100)
         .background(Color.orange)
   Text("second item")
         .frame(width: 120, height: 70)
         .background(Color.red)
    Text("third item")
         .frame(width: 80, height: 40)
         .background(Color.gray)
}