Yellow with black or gray look very high-tech. Cool and refreshing. The water, the sky, the air, and the sea. Dark blue combined with bright, contrasting colors give a sharp, modern look. The nature, the green field, the trees.
Green works well in most combinations of green shades.
Green with yellow or white makes bright, refreshing combination. Dark shades of green suggest relaxation. Yellow and red. White and red. Yellow and black.