ERROR in ./node_modules/raw-loader!./node_modules/postcss-loader/lib??embedded!./node_modules/sass-loader/lib/loader.js??ref--8-3!./src/app/@theme/styles/styles.scss
Module build failed: 
  @mixin hover-border($color) {
        ^
      Mixins may not be defined within control directives or other mixins.
      in /home/richard/workspace/ngx-admin/node_modules/@nebular/theme/components/checkbox/_checkbox.component.theme.scss (line 8, column 10)

直接安装node-sass@4.8.1

npm i node-sass@4.8.1