     //ViewController Ends here
 }
 
+
+
+// MARK: - FlatUIColors Extension
 extension FlatUIColors {
     public static func randomFlatColor()->UIColor {
         let colors = [FlatUIColors.turquoiseColor(), FlatUIColors.greenSeaColor(), FlatUIColors.emeraldColor(), FlatUIColors.nephritisColor(), FlatUIColors.peterRiverColor(), FlatUIColors.belizeHoleColor(), FlatUIColors.amethystColor(), FlatUIColors.wisteriaColor(), FlatUIColors.wetAsphaltColor(), FlatUIColors.midnightBlueColor(), FlatUIColors.sunflowerColor(), FlatUIColors.flatOrangeColor(), FlatUIColors.carrotColor(), FlatUIColors.pumpkinColor(), FlatUIColors.alizarinColor(), FlatUIColors.pomegranateColor(), FlatUIColors.cloudsColor(), FlatUIColors.silverColor(), FlatUIColors.concreteColor(), FlatUIColors.asbestosColor()]

            if color == colorPair.colorA {complementaryColor = colorPair.colorB}
            if color == colorPair.colorB {complementaryColor = colorPair.colorA}
        }
        
        return complementaryColor
    }
    
}


    // change background color when user touches cell
    func collectionView(collectionView: UICollectionView, didHighlightItemAtIndexPath indexPath: NSIndexPath) {
        let cell = collectionView.cellForItemAtIndexPath(indexPath)
        cell?.backgroundColor = FlatUIColors.pairedColorForColor(cell?.backgroundColor)
    }
    
    // change background color back when user releases touch
    func collectionView(collectionView: UICollectionView, didUnhighlightItemAtIndexPath indexPath: NSIndexPath) {
        let cell = collectionView.cellForItemAtIndexPath(indexPath)
        cell?.backgroundColor = FlatUIColors.pairedColorForColor(cell?.backgroundColor)
    }
    
    // MARK: === UICollectionViewDelegateFlowLayout ===
