sass @ mixins

Question

Metrnic 的源码，运行gulp sass报错：Import directives may not be used within control directives or mixins

[17:17:06] Using gulpfile E:\webpack_workspace\metronic_v4.5.6\theme\gulpfile.js
[17:17:06] Starting 'sass'...
[17:17:06] Finished 'sass' after 17 ms

events.js:160
      throw er; // Unhandled 'error' event
      ^
Error: sass\global\_components.scss
Error: Import directives may not be used within control directives or mixins.
        on line 7 of sass/global/_components.scss
>> @import 'components/_reset-rounds';
   ^

    at options.error (E:\webpack_workspace\metronic_v4.5.6\theme\node_modules\node-sass\lib\index.js:286:26)

sass-loader和sass都已安装了