         return 0
     }()
     
+    /**
+     * CollectionView content offset is determined by status bar and navigation bar height
+    */
     lazy private var topItemOffset:CGFloat = {
         return -(self.statusBarHeight + self.navbarHeight)
     }()
     
     private var searchBarHeight:CGFloat = 44
+    private var marginValue:CGFloat = 8
+
+    private var softAnimationDuration = 0.2
+    private var accurateAnimationDuration = 0.5
     
     // TODO: in future replace managerWithDummyData()
     override func viewWillAppear(animated: Bool) {

        if animated {
            UIView.beginAnimations("cancel", context: nil)
            UIView.setAnimationDelay(0)
            UIView.setAnimationDuration(0.5)
            UIView.setAnimationCurve(.EaseOut)
            
        }
        if let navigation = navigationController?.navigationBar {
            
            let top = -self.topItemOffset + self.searchBarHeight
            
            self.decksCollectionView.contentInset = UIEdgeInsets(top: top, left: 0, bottom: 0, right: 0)
            self.decksCollectionView.contentOffset.y = -top
            
            navigation.frame.origin.y = self.statusBarHeight
            

        if animated {
            UIView.beginAnimations("cancel", context: nil)
            UIView.setAnimationDelay(0)
            UIView.setAnimationDuration(accurateAnimationDuration)
            UIView.setAnimationCurve(.EaseOut)
            
        }
