  Considering the density dependence of quark masses, we investigate the
color-flavor-locked matter and its stability relative to the ( unpaired )
strange quark matter. We find that, when the current mass of strange quark
$m_s$ is small, the strange quark matter remains stable for the moderate baryon
densities. When $m_s$ is large, the gapless phase of the color-flavor-locked
matter is found to be difficult to be stable. A schematic phase diagram of
three-flavor quark matter is presented, in which the color-flavor-locked phase
region is suppressed in comparison with the previous results.
