以前学习时候用过现在主要就前几个
https://alpha.wallhaven.cc/
http://www.pixiv.net/
http://www.netbian.com/
https://www.cgwallpapers.com/
https://www.wallpaperup.com/
https://unsplash.com/t/wallpapers
https://www.desktopnexus.com/
https://www.wallpaperup.com/
http://wallpaperim.net/index/category/2-3d_wallpapers