Design OK, but I will look better with a white bitcoin symbol.

That symbol is not as striking as it should be, because that gray color has almost the same brightness ("Y component") as the red backgound.  The brain uses only the brightness channel to identify outllines, ignoring the color information.  Therefore, it is possible to create texts with grey lettering on colored background that are visible but totally unreadable -- if the background happens to have the same Y as the font.  (But it suffices maybe a 0.2% difference in Y to make the outline visible again.)