Light blue is concidered the color of thinking. Our mind wanders the imagined endless air above us in search for thoughts or a memories, lines we know is there in our memory, we even cast a glancing eye up to the sky in search. Colors have profound emotional meaning. The color of the sky is the lightest of the colors, fading into white, into nothingness openness positive and optimism. Dark blue always fades into an uncertant unknowing black.
This why the name.