This design work is a multi-functional book cover that can be transformed according to the use requirements. It can be turned into a small office platform and desktop tablet computer technology rack, which is used to put other office supplies such as mobile phones, tablet computers and writing notebooks. It mainly serves office workers when they do not have a working platform during their work. Users can use it to spell out a small working platform to assist office at any time, improve work effectiveness and solve the problem of inconvenience in finding office space on frequent business trips or outdoor offices. When indoors, it can be turned into a desktop storage board, making the usually messy work desktop clean and orderly. When the user is not in use, it can be stored in the same size as a book and can be placed in bookshelves, drawers, office bags, etc. without taking up too much space.