Set of blue abstract colorful smooth blurred vector backgrounds for design of mobile app, book cover, booklet, background, poster, web sites, annual reports, business infographic, social media 用于移动应用程序、书籍封面、小册子、背景、海报、网站、年度报告、商业信息图、社交媒体设计的一组蓝色抽象彩色平滑模糊背景的矢量插图