UI update

LeCountdown/LeCountdownApp.swift

@@ -20,6 +20,10 @@ struct LeCountdownApp: App {
 
     @UIApplicationDelegateAdaptor(AppDelegate.self) var appDelegate
     
+    init() {
+        UITabBar.appearance().backgroundColor = UIColor(white: 0.96, alpha: 1.0)
+    }
+    
     var body: some Scene {
         WindowGroup {
             TabView {