 public enum PopupCollectionViewControllerOption {
     case layout(PopupCollectionViewController.PopupLayout)
     case animation(PopupCollectionViewController.PopupAnimation)
-    case overlayColor(UIColor)
     case overlayLayer(CALayer)
     case popupHeight(CGFloat)
     case cellWidth(CGFloat)

                self.layout = value
            case .animation(let value):
                self.animation = value
            case .overlayColor(let value):
                self.overlayColor = value
            case .overlayLayer(let value):
                self.overlayLayer = value
            case .popupHeight(let value):

    // Custom Property
    fileprivate var layout: PopupLayout = .center
    fileprivate var animation: PopupAnimation = .slideUp
    fileprivate lazy var overlayLayer: CALayer = {
        let layer = CALayer()
        layer.backgroundColor = UIColor(white: 0.0, alpha: 0.4).cgColor
        return layer
    }()
    fileprivate var popupHeight: CGFloat = 400
    fileprivate var cellWidth: CGFloat = 300
    fileprivate var contentEdgeInsets: CGFloat = 24
