let myDynamicColor = UIColor { (traitCollection: UITraitCollection) -> UIColor in
    switch traitCollection.userInterfaceStyle {
    case .unspecified, .light: return UIColor(red: 220, green: 220, blue: 220, alpha: 1.0)
    case .dark: return UIColor(red: 0, green: 0, blue: 0, alpha: 1.0)
    }
}