78 Steam profile backgrounds that are mostly orange and anime, ranked by community votes.
Every background is downscaled and each pixel is put into one of ten colour groups. A background is listed under a colour when that colour covers a large part of the picture, so the lists reflect what you actually see, not the game's name.
Buy it on the Steam Community Market or in the Points Shop. Then open your profile, click Edit Profile → Profile Background, pick it and save.
New backgrounds are analysed automatically a few times a day; a background appears in the colour lists once its picture has been checked.