  The flavor structure of quarks and leptons is not yet fully understood, but
it hints a more fundamental theory of non-universal generations. We therefore
propose a simple extension of the Standard Model by flipping (i.e., enlarging)
the hypercharge $U(1)_Y$ to $U(1)_X\otimes U(1)_N$ for which both $X$ and $N$
depend on generations of both quark and lepton. By anomaly cancellation, this
extension not only explains the existence of just three fermion generations as
observed but also requires the presence of a right-handed neutrino per
generation, which motivates seesaw neutrino mass generation. Furthermore, in
its minimal version with a scalar doublet and two scalar singlets, the model
naturally generates the measured fermion-mixing matrices while it successfully
accommodates several flavor anomalies observed in the neutral meson mixings,
$B$-meson decays, lepton-flavor-violating processes of charged leptons, as well
as satisfying constraints from particle colliders.
