https://material.io/icons/
图标素材,Access over 900 material system icons, available in a variety of sizes and densities, and as a web font.,
「Favicon.io」是一个协助站...
http://www.iconarchive.com
http://simplelineicons.com
https://fontawesome.com/icons
http://www.iconfont.cn
https://www.iconfinder.com
「Favicon.io」是一个协助站...