.net colors

            var c1 = System.Drawing.Color.Aqua;
            var c2 = SystemColors.ActiveBorderBrush;
            var c3 = System.Windows.Media.Color.FromRgb(3, 0, 0);

in Wpf gibts vordefinierte Brushes:
System.Windows.Media.Brushes ... eine Liste von SolidColorBrushes