I don't know about the colour aspect, but one of the most marvelous books I
know is George MacDonald's AT THE BACK OF THE NORTH WIND. Blue or
other colours may be part of the description of the wind, but it has
been a few years since I last read it. Perhaps you might look this
up. Your project sounds wonderful!
I just finished the first draft of a memoir of my very strange childhood,
when I was taken from the backwoods of Texas to be a child actress in
Hollywood. In the memoir, I mentioned MacDonald's books because it felt
like they saved my life during some very confusing years. Some of his books are
aimed at a young audience, but even those might be of interest to
adults who have never read them. His fantasy was real - not like Hollywood.