How can I change BackColor of TaskDialog bar to something custom?

            RadTaskDialogPage page = new RadTaskDialogPage();
        
            page.Caption = "Window Title";
            page.Heading = "Main instruction";
            page.Text = "Main text here...";
            page.Icon = RadTaskDialogIcon.ShieldSuccessGreenBar;
            page.Icon.SvgImage = RadTaskDialogIcon.GetSvgImage(RadTaskDialogIconImage.FlatShieldSuccess, new Size(32, 32));

            page.HeaderLayout.BackgroundElement.BackColor = Color.Red; ;
            page.HeaderLayout.BackgroundElement.GradientStyle = GradientStyles.Solid;
            
            RadTaskDialog.ShowDialog(page);