public void ShowStartDialog(string message)
        {
            var card = new Card {
                Padding = new Thickness(32), Margin = new Thickness(16), Width = 350
            };
            var stackPanel = new StackPanel {
                HorizontalAlignment = HorizontalAlignment.Center
            };
            var textBlock = new TextBlock {
                Text = message, TextWrapping = TextWrapping.Wrap
            };

            var buttonStack = new StackPanel {
                Orientation = Orientation.Horizontal, HorizontalAlignment = HorizontalAlignment.Center
            };
            var yesButton = new Button {
                Content = "YES", Width = 100
            };
            var noButton = new Button {
                Content = "NO", Width = 100
            };

            var btnstyle = Application.Current.FindResource("MaterialDesignFlatButton") as Style;

            if (btnstyle != null)
            {
                yesButton.Style = btnstyle;
                noButton.Style  = btnstyle;
            }
            yesButton.Command = DialogYesPrompt;
            noButton.Command  = DialogNoPrompt;

            stackPanel.Children.Add(textBlock);
            buttonStack.Children.Add(yesButton);
            buttonStack.Children.Add(noButton);
            stackPanel.Children.Add(buttonStack);
            card.Content = stackPanel;

            DH?.ShowDialog(card);
        }