vue style使用了scss等，报错

* !!vue-style-loader!css-loader?{"sourceMap":true}!../node_modules/vue-loader/lib/style-compiler/index?{"vue":true,"id":"data-v-7ba5bd9
0","scoped":false,"hasInlineConfig":false}!sass-loader?{"sourceMap":true}!../node_modules/vue-loader/lib/selector?type=styles&index=0!.
/App.vue in ./src/App.vue

To install it, you can run: npm install --save !!vue-style-loader!css-loader?{"sourceMap":true}!../node_modules/vue-loader/lib/style-co
mpiler/index?{"vue":true,"id":"data-v-7ba5bd90","scoped":false,"hasInlineConfig":false}!sass-loader?{"sourceMap":true}!../node_modules/
vue-loader/lib/selector?type=styles&index=0!./App.vue

css laoder没安装
安装
npm install sass-loader --save-dev
npm install node-sass --save-dev
npm install css-loader style-loader --save-dev