This one is from tom, who was also involved in the original video. This design is all clear skies and rainbows! 
— Website description[1]
reverse rainbow (逆さまレインボー Sakasama Reinbō?) is an Outfit for Megurine Luka.
Description[]
The Outfit's attire consists of a long white short-sleeved coat with pink inner-fabric, a black collar with a blue stripe, black end sleeves, and a pink bow on the back, a gold woodwind-esque ornament with a blue jewel piece attached to the coat, a long white shirt with gold stripes on slits on the sides, a brown skirt, teal three-finger rings with a white and teal poppy on the middle fingers and two dandelions on the index and ring fingers, black stockings, and dark yellow boots with small blue droplets on each side and brown soles. Additionally, Luka wears white headphones with a rainbow on each of the side handles and pink eighth notes (♪) on the earpads.
Game appearances[]
The Outfit first appeared in Hatsune Miku and Future Stars: Project Mirai where it can be unlocked by clearing "reverse rainbow" twice on Hard difficulty and can be bought for 5000 Mirai Points. It returns in Hatsune Miku: Project Mirai 2 and Project Mirai DX where it can be unlocked by clearing the aforementioned song on any difficulty and can be bought for 5000 Mirai Points in Project Mirai 2 and 3000 Mirai Points in Project Mirai DX.