diff --git a/OpenSourceController/Classes/Controller/OpenSourceViewController.swift b/OpenSourceController/Classes/Controller/OpenSourceViewController.swift
index d0d7b74..52e4075 100644
--- a/OpenSourceController/Classes/Controller/OpenSourceViewController.swift
+++ b/OpenSourceController/Classes/Controller/OpenSourceViewController.swift
@@ -76,18 +76,24 @@ class OpenSourceViewController: UITableViewController {
         self.tableView.dataSource = self
         self.tableView.delegate = self
         self.tableView.separatorStyle = .singleLine
-        self.tableView.backgroundColor = config.uiConfig.backgroundColor
+        if let backgroundColor = self.config.uiConfig.backgroundColor {
+            self.tableView.backgroundColor = backgroundColor
+        }
 
         // Navigation bar 
-        self.navigationController?.navigationBar.barTintColor = self.config.uiConfig.barTintColor
-        let attribut = [NSForegroundColorAttributeName: self.config.uiConfig.titleColor]
-        self.navigationController?.navigationBar.titleTextAttributes = attribut
+        if let tintColor = self.config.uiConfig.barTintColor {
+            self.navigationController?.navigationBar.barTintColor = tintColor
+        }
+        if let textColor = self.config.uiConfig.titleColor {
+            let attribut = [NSForegroundColorAttributeName: textColor]
+            self.navigationController?.navigationBar.titleTextAttributes = attribut
+        }
 
         // Close button (on the right corner of navigation bar)
         let closeButton = UIBarButtonItem(barButtonSystemItem: .stop,
                                           target: self,
                                           action: #selector(self.closePicker))
-        closeButton.tintColor = config.uiConfig.closeButtonColor
+        closeButton.tintColor = config.uiConfig.closeButtonColor ?? UIColor.black
         self.navigationItem.rightBarButtonItem = closeButton
 
         // Loading indicator
diff --git a/OpenSourceController/Classes/Model/OpenSourceControllerConfig.swift b/OpenSourceController/Classes/Model/OpenSourceControllerConfig.swift
index 394fbcb..e4552f0 100644
--- a/OpenSourceController/Classes/Model/OpenSourceControllerConfig.swift
+++ b/OpenSourceController/Classes/Model/OpenSourceControllerConfig.swift
@@ -12,22 +12,22 @@ public struct OpenSourceControllerConfig {
     /// Sub-stuct holding configuration relevant to UI presentation ! 
     public struct UIConfig {
         /// Will be applied to the navigation bar 
-        public var barTintColor: UIColor = UIColor(red: 246/255.0, green: 246/255.0, blue: 246/255.0, alpha: 1.0)
+        public var barTintColor: UIColor?
 
         /// Will be applied to the navigation bar 
-        public var backgroundColor: UIColor = UIColor(red: 246/255.0, green: 246/255.0, blue: 246/255.0, alpha: 1.0)
+        public var backgroundColor: UIColor? 
 
         /// Will be applied to licence text
-        public var licenceBackgroundColor: UIColor = UIColor.white
+        public var licenceBackgroundColor: UIColor?
 
         /// Will be applied to the navigation bar 
-        public var closeButtonColor: UIColor = UIColor.black
+        public var closeButtonColor: UIColor?
 
         /// Will be applied to licence text
-        public var licenceTextColor: UIColor = UIColor.black
+        public var licenceTextColor: UIColor?
 
         /// Will be applied to licence text
-        public var titleColor: UIColor = UIColor.black
+        public var titleColor: UIColor?
     }
 
     /// Will be applied to the navigation bar title
diff --git a/OpenSourceController/Classes/View/OpenSourceTableViewCell.swift b/OpenSourceController/Classes/View/OpenSourceTableViewCell.swift
index 9be19c2..0694dfe 100644
--- a/OpenSourceController/Classes/View/OpenSourceTableViewCell.swift
+++ b/OpenSourceController/Classes/View/OpenSourceTableViewCell.swift
@@ -64,6 +64,8 @@ class OpenSourceTableViewCell: UITableViewCell {
         self.textLabel?.textColor = config.uiConfig.licenceTextColor
 
         // Background 
-        self.backgroundColor = config.uiConfig.licenceBackgroundColor
+        if let backgroundColor = config.uiConfig.licenceBackgroundColor {
+            self.backgroundColor = backgroundColor
+        }
     }
 }