CERO C and higher and Nintendo 3DS & Wii U banners:
If a Nintendo 3DS or Wii U game is given the age rating of C (15+) ot higher, it uses a darker shade then the normal console tittle banner on the games packaging.
In the case for Nintendo 3DS, the backgorund of the 3DS logo is black for CERO C or higher, compared to the deafult white background for B or lower, and all international versions:
Same applyes to the Wii U, but instead of white/black its a from the default light blue gradent to a dark blue greadent for CERO C and higher (minimun age of 15 or higher):
