  Influence of magic numbers on nuclear radii is investigated via the
Hartree-Fock-Bogolyubov calculations and available experimental data. With the
$\ell s$ potential including additional density-dependence suggested from the
chiral effective field theory, kinks are universally predicted at the
$jj$-closed magic numbers and anti-kinks (\textit{i.e.} inverted kinks) are
newly predicted at the $\ell s$-closed magic numbers, both in the charge radii
and in the matter radii along the isotopic and isotonic chains where nuclei
stay spherical. These results seem consistent with the kinks of the charge
radii observed in Ca, Sn and Pb and the anti-kink in Ca. The kinks and the
anti-kinks could be a peculiar indicator for magic numbers, discriminating
$jj$-closure and $\ell s$-closure.
