Material Design 官方图标字体，风格统一、覆盖面广。
引用代码
<link rel="stylesheet" href="https://cdn.bootcdn.net/ajax/libs/material-design-icons/3.0.1/iconfont/material-icons.min.css">资源地址
https://cdn.bootcdn.net/ajax/libs/material-design-icons/3.0.1/iconfont/material-icons.min.css