This cover is a redrawn version of the cover of Supergirl (DC, 1996 series) #75 and a homage to the cover of Action Comics (DC, 1938 series) #252.
Art is an homage to Action Comics (DC, 1938 series) #252 (May 1959).
Cover is an homage to the cover of Crisis on Infinite Earths (DC, 1985 series) #7 (October 1985).