  A flavor dependent kernel is constructed based on the rainbow-ladder
truncation of the Dyson-Schwinger and Bethe-Salpeter equation approach of
Quantum Chromodynamics. The quark-antiquark interaction is composed of a flavor
dependent infrared part and a flavor independent ultraviolet part. Our model
gives a successful and unified description of the light, heavy and heavy-light
ground pseudoscalar and vector mesons. For the first time, our model shows that
the infrared enhanced quark-antiquark interaction is stronger and wider for the
lighter quark.
