The description of the CSS reference (http://docs.oracle.com/javase/8/javafx/api/javafx/scene/doc-files/cssref.html#typecolor) for "derive" says:

"A value of -100% means completely black, 0% means no change in brightness, and 100% means completely white."

This is wrong. I tried it out using derive(red, 125%) and still it is not "completely white" but just "pale red"!