I want a green for "correct answer" and a red for "wrong answer". My current choice is
rgb(144, 238, 144) for the green and
rgb(250, 128, 114) for the red. (See wikilearner.net/wiki for the colours in action.)
I have been told that these colors are very close in contrast, making it difficult for a person with red-green color-blindness. What would be a better choice?