                       initialSpringVelocity: 0.5,
                       options: UIView.AnimationOptions.allowUserInteraction,
                       animations: {
                        self.imageTutorialHand.alpha = alpha
        }, completion: handler)
    }
    
    private func animateHandMove(offset: CGFloat, delay: TimeInterval, duration: TimeInterval, handler: ((Bool)->Void)?) {
        
        let transform = imageTutorialHand.transform.translatedBy(x: 0.0, y: -offset)
        
        UIView.animate(withDuration: duration,
                       delay: delay,