I just finished Project2 but when I added the borders to the flag buttons they don't outline the flag images perfectly. It seems like there is some padding between the image and the border. I tried to look through the Attribute Inspector for the buttons to see if I could change it there, but I'm not seeing it.

How can I remove the extra space between the button image and the border?

My code looks like this if it helps at all

import UIKit

class ViewController: UIViewController {
    @IBOutlet var button1: UIButton!
    @IBOutlet var button2: UIButton!
    @IBOutlet var button3: UIButton!

    var countries = [String]()
    var score = 0
    var correctAnswer = 0
    var currentQuestion = 1

    override func viewDidLoad() {
        super.viewDidLoad()

        countries += ["estonia", "france", "germany", "ireland", "italy", "monaco", "nigeria", "poland", "russia", "spain", "uk", "us"]

        button1.layer.borderWidth = 1
        button2.layer.borderWidth = 1
        button3.layer.borderWidth = 1

        button1.layer.borderColor = UIColor.lightGray.cgColor
        button2.layer.borderColor = UIColor.lightGray.cgColor
        button3.layer.borderColor = UIColor.lightGray.cgColor

        askQuestion()
    }

    func askQuestion(action: UIAlertAction! = nil) {
        countries.shuffle()
        correctAnswer = Int.random(in: 0...2)
        title = "\(countries[correctAnswer].uppercased()) : \(score)"

        button1.setImage(UIImage(named: countries[0]), for: .normal)
        button2.setImage(UIImage(named: countries[1]), for: .normal)
        button3.setImage(UIImage(named: countries[2]), for: .normal)
    }

    func newGame(action: UIAlertAction! = nil) {
        score = 0
        currentQuestion = 1
        askQuestion()
    }

    @IBAction func buttonTapped(_ sender: UIButton) {

        if sender.tag == correctAnswer {
            title = "Correct"
            score += 1
        } else {
            title = "Wrong"
            score -= 1
        }

        var alertActionTitle = "Continue"
        var alertMessage = "That is the flag of \(countries[sender.tag].uppercased())\nQuestion: \(currentQuestion)/10\nYour score is: \(score)"
        var alertHandler = askQuestion

        if currentQuestion < 10 {
            currentQuestion += 1
        } else {
            alertActionTitle = "New Game"
            alertMessage = "Game Over\nFinal score: \(score)"
            alertHandler = newGame
        }

        let ac = UIAlertController(title: title, message: alertMessage, preferredStyle: .alert)
        ac.addAction(UIAlertAction(title: alertActionTitle, style: .default, handler: alertHandler))
        present(ac, animated: true)
    }
}