override func viewDidLoad() {
Timer.scheduledTimer(timeInterval: 5.0, target: self, selector: #selector(ViewController.startRedBalloon), userInfo: nil, repeats: true)
}

@objc func startRedBalloon() {
        let xOrigin = arc4random_uniform(208) + 1
        let xEnding = arc4random_uniform(208) + 1

        redBalloon.isHidden = false
        redBalloon.image = UIImage(named: "redBalloon")
        redBalloon.contentMode = .scaleAspectFit
        redBalloon.frame = CGRect(x: Int(xOrigin), y: 667, width: Int(redBalloon.frame.size.width), height: Int(redBalloon.frame.size.height))

        let animRed = UIViewPropertyAnimator(duration: 5, timingParameters: UICubicTimingParameters(animationCurve: .easeIn))
        animRed.addAnimations {
            self.redBalloon.frame = CGRect(x: Int(xEnding), y: -192, width: 100, height: 116)
        }
        animRed.addCompletion { _ in
            self.endGame()
        }

        let imageTapRed = UITapGestureRecognizer(target: self, action: #selector(imageTappedRed))
        redBalloon.isUserInteractionEnabled = true
        redBalloon.addGestureRecognizer(imageTapRed)
        animRed.startAnimation()
    }

@objc func imageTappedRed(_ sender: UITapGestureRecognizer) {
        redBalloon.image = UIImage(named: "redShreds")
        UIViewPropertyAnimator(duration: 2, curve: .easeOut, animations: {
            self.redBalloon.alpha = 0.0
        }).startAnimation()
        score += 1
    }