These games are remakes of
The Great Giana Sisters,
a 1987 Commodore 64 game that was in turn a clone of Super Mario Bros,
so close that Nintendo pressured the publisher (Rainbow Arts) to
withdraw the game from sale.
Giana Sisters was originally released at the Mekka & Symposium 1998,
it was the winning entry in the 32k game competition. It runs at an
uncommon 360×240 resolution (another game that used it is
uses the graphics of the 16-bit (Amiga, Atari ST) port of
The Great Giana Sisters, slightly enhanced. The higher resolution allows
for a black border as in the original Commodore 64 version.
The full game, with further enhanced graphics, more levels and other
improvements was released later in the same year, and finally, for
Christmas, the X-Mas'98 Special Edition. The next year Rainer Sinsch
started working on a Windows game that sticks less strictly to the
Commodore 64 original, Giana Worlds.
If you like Giana Sisters, you might like
Mario & Luigi.