Why my iPhone is showing up as replaced.

Hello guys I bought a iphone 6s 64gb space Grey. It is sprint locked and when I entre my imei or serial no in any online iphone checking device it shows up as an iphone 6s but in an rose gold colour. Secondly my home button black and home buttons can only be changed by apple or they loose there fingerprint sensor but mine is working but it should be in white colour.last when I boot up the device the apple logo is white and background is black where it has to be opposite as per of a rose gold iphone 6s.pls can anyone explain this to me?