Webpack executes npm run dev error report

vue.js running npm.run.dev error

ERROR in ./node_modules/mint-ui/lib/style.css (./node_modules/css-loader!./node_modules/autoprefixer-loader!./node_modules/mint-ui/lib/style.css)
Module build failed (from ./node_modules/autoprefixer-loader/index.js):
TypeError: Cannot read property "context" of undefined
    at Object.module.exports (C:\Users\99680\Desktop\web\cms\node_modules\autoprefixer-loader\index.js:21:53)
 @ ./node_modules/mint-ui/lib/style.css 2:14-99 21:1-42:3 22:19-104
 @ ./src/main.js
 @ multi (webpack)-dev-server/client?http://localhost:9999 (webpack)/hot/dev-server.js ./src/main.js

ERROR in ./src/components/home/home.vue?vue&type=style&index=0&lang=css& (./node_modules/css-loader!./node_modules/vue-loader/lib/loaders/stylePostLoader.js!./node_modules/autoprefixer-loader!./node_modules/vue-loader/lib??vue-loader-options!./src/components/home/home.vue?vue&type=style&index=0&lang=css&)
Module build failed (from ./node_modules/autoprefixer-loader/index.js):
TypeError: Cannot read property "context" of undefined
    at Object.module.exports (C:\Users\99680\Desktop\web\cms\node_modules\autoprefixer-loader\index.js:21:53)
 @ ./src/components/home/home.vue?vue&type=style&index=0&lang=css& (./node_modules/style-loader!./node_modules/css-loader!./node_modules/vue-loader/lib/loaders/stylePostLoader.js!./node_modules/autoprefixer-loader!./node_modules/vue-loader/lib??vue-loader-options!./src/components/home/home.vue?vue&type=style&index=0&lang=css&) 2:14-293 21:1-42:3 22:19-298 @ ./src/components/home/home.vue?vue&type=style&index=0&lang=css&
 @ ./src/components/home/home.vue
 @ ./src/main.js
 @ multi (webpack)-dev-server/client?http://localhost:9999 (webpack)/hot/dev-server.js ./src/main.js

version is "webpack": "^ 4.16.5", "webpack-cli": "^ 3.1.0", "webpack-dev-server": "^ 3.1.5",

main.js

"use strict";
import Vue from "vue";

import vueRouter from "vue-router";

Vue.use(vueRouter);
import Home from "./components/home/home.vue";

let router = new vueRouter({
    routes: [
        {path: "/", redirect: {name: "home"}},//
        {name: "home", path: "/home", component: Home}
    ]
});

import Mint from "mint-ui";
import "mint-ui/lib/style.css";
Vue.use(Mint);

import Axios from "axios";
Vue.prototype.$ajax=Axios;

import App from "./app.vue";

new Vue({
    el: ".app",
    router:router,
    render: c => c(App)
})

solve it, everybody, what"s wrong