public Color CalcNavColor(int d)
{
Color clr = SystemColors.Highlight;
int r = clr.R, g = clr.G, b = clr.B;
int max = Math.Max(Math.Max(r, g), b);
int delta = 0x23 + d;
int maxDelta = (255 - (max + delta));
if (maxDelta > 0) maxDelta = 0;
r += (delta + maxDelta + 5);
g += (delta + maxDelta);
b += (delta + maxDelta);
if (r > 255) r = 255;
if (g > 255) g = 255;
if (b > 255) b = 255;
return Color.FromArgb(Math.Abs(r), Math.Abs(g), Math.Abs(b));
}