Color is not claimed as a feature of the mark.
The mark consists of The T.A.N.K text is surrounded by a custom image of a tank top, as well as spelling of acronym (Truth, Adventure, Nature, Knowledge). All text and outline are black (RGB 0,0,0) by default; for usage on dark fabric, reverse image (white rgb 255, 255, 255) - exact same formatting acceptable variation..
TANK GIRLS
"T.A.N.K has become distinctive of the goods/services, as demonstrated by the attached evidence."