Object appearing in grayscale in game?

Hi! So sorry if this has been asked before, but I just finished making my first (decent) piece of CC and everything seems to show up fine in S4S, but when I load the game the object is in black and white. What am I doing wrong here? Thank you so much!

Here's a link to the package file if that helps: www.mediafire.com/file/587wdn4vc47sax7/Toadstool1.package/file