It sure doesn’t sound like a Kajiura arrange (which the official site says she did). (Uh, I made a mistake earlier. It’s composed by Kajiura and arranged by someone else, which explains why it doesn’t sound like a Kajiura track. >_< ) The vocals don't sound like Mashiro/Yukana either (which the official site says she did). LOL. Pretty crappy song if you ask me.

『笑顔の色は虹の色』 (full version)