Vivo - Pastel (?)
Oscuro - Claro
Alto - Bajo
Flojo - Apretado
I don't understand the first one, since that part has nothing to do with it. For me, the antonym is "vivo" is "muerto".
Perhaps he is referring to the colors: a bright color and a pastel color. But I still don't quite understand the analogy.
MissSpanish