Chroma Hills_Problem with sign text's color

Bug report: I use the texture pack Chroma Hills.

Sign text's color can now be changed with any of the 16 dyes, but the colors of text are indistinctive in comparison with the previous version.For example:  the yellow color (§g) is rather dark brownish-yellow (see the printscreen below; state "before" on the right side, state "after" on the left side).