1、新增postcss-loader，注意要放到css-loader後，sass-loader之前，不然的話使用@import方式引入會無效

 {
        test: /\.(s[ac]ss)$/,
        use: [
          "style-loader",
          'css-loader',
          "postcss-loader",
          "sass-loader"
        ]
      }

2、專案根目錄新增postcss.config.js

module.
 
exports = {
  plugins: [
    require("autoprefixer")
  ]
};

3、package.json中新增

 "browserslist": [
    "defaults",
    "not ie <= 8",
    "last 2 versions",
    "> 1%",
    "iOS >= 7",
    "Android >= 4.0"
  ]