     
     open var dismissCompletion: (() -> Void)?
     
+    open var backgroundColor: UIColor = .black {
+        didSet {
+            view.backgroundColor = backgroundColor
+        }
+    }
+    
     open lazy var session: URLSession = {
         let configuration = URLSessionConfiguration.ephemeral
         return URLSession(configuration: configuration, delegate: nil, delegateQueue: OperationQueue.main)

    // MARK: Setups
    
    fileprivate func setupView() {
        view.backgroundColor = UIColor.black
    }
    
    fileprivate func setupScrollView() {

            
            scrollView.center = getChanged()
            panViewAlpha = 1 - getProgress()
            view.backgroundColor = backgroundColor.withAlphaComponent(panViewAlpha)
            gesture.setTranslation(CGPoint.zero, in: nil)

        case .ended:
