How do I set color values (e.g. for RGB, CMYK color space)?

Q: I have encountered one difficulty with assigning RGB color to a
text or path.
I intended to use R=37, G=64, B=97 parameters but result was
unexpected. The font just become transparent.

The code I have use fore coloring text:

                element = builder.CreateTextRun("some text");

                ColorPt blueColor = new ColorPt(37, 64, 97);

Wherever I assign all three parameters of ColorPt object the code
return transparent text.
What is the best way to assign a color to the text using RGB color
space family?
A: In PDF all color component are floating point numbers in the range
between 0.0 to 1.0. To correct the problem simply divide the colorants
by 255.0. For example:

element.GetGState().SetFillColor(new ColorPt(37/255.0, 64/255.0,