vant/lib/vant-css/index.css in ./src/main.js

vant组件引用报错 :

This dependency was not found:
 * vant/lib/vant-css/index.css in ./src/main.js
To install it, you can run: npm install --save  vant/lib/vant-css/index.css

解决办法 ：

在index.html文件中以cdn的形式，引入css样式：

<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/vant@1.6/lib/index.css">