Base code is from Paul Hudson's 100 Days of SwiftUI.

Assignment:

1. Add an @State property to store the user’s score, modify it when they get an answer right or wrong, then display it in the alert.
2. Show the player’s current score in a label directly below the flags.
3. When someone chooses the wrong flag, tell them their mistake in your alert message – something like “Wrong! That’s the flag of France,” for example.