Background material that may be used in summer 41 is a vector of kabu author. This vector includes fireworks, Large wheel, Fireworks, Large sky, Light tags. To download vector (JPG, SVG, PNG, AI/EPS types) you need to register the account and log in.
As the free account, you can download for free with some limits.
As the premium account, you can download unlimited, no waiting time, etc. Enjoin premium membership at here