Improve UI

LeCountdown/Views/StartView.swift

@@ -143,8 +143,11 @@ struct DurationSheetView: View {
     
     var body: some View {
         VStack(alignment: .leading) {
-            Text("Duration").padding([.leading, .top])
+            NavigationStack {
                 TimePickerView(duration: self.$duration)
+                    .navigationTitle("Duration")
+                    .navigationBarTitleDisplayMode(.inline)
+            }
             .presentationDetents([.height(240.0)])
         }
     }
@@ -164,8 +167,12 @@ struct SoundButtonView: View {
             Image(systemName: "music.note")
             Text(self.soundModel.soundSelection(short: true))
         }.sheet(isPresented: $showSoundSheet) {
+            NavigationStack {
                 PlaylistsView(model: self.soundModel,
                                   catalog: .ring)
+                .navigationTitle("Sounds")
+                .navigationBarTitleDisplayMode(.inline)
+            }
             .presentationDetents([.height(320.0)])
         }
     }