  We compute Przyjalkowski-Shramov's resolution of the Calabi-Yau
compactification of Givental's mirror Landau-Ginzburg model of the quadric
hypersurfaces. We deduce the Picard-Fuchs equation for the narrow periods,
which mirror the ambient quantum cohomology of quadric hypersurfaces. Then by
an indirect approach using the irreducibility of the narrow Picard-Fuchs
operator we deduce the Picard-Fuchs equation of the broad period, which mirrors
the quantum cohomology of quadric hypersurfaces involving primitive cohomology
classes. The result suggests a natural choice of the opposite space in
Barannikov's construction of Frobenius manifolds. Finally, we show an
isomorphism between the Frobenius manifolds associated with the quantum
cohomology of a quadric hypersurface and its mirror Landau-Ginzburg model.
