How can I store all scss file that I import to js/vue files into a css file?

Hi, I want to all scss files that I import to may vue files store in a css file. How can I do it? I am using laravel v6. My laravel resources app structure is like this:

• resources
  • vuesin
    • components
      • Tree
        • _tree.scss
        • Tree.vue
        • ...

and in Tree.vue I do:

...

<script>
    import './_tree.scss';
    ...
</script>

Every thing work good. But I don't know how to config my laravel mix to store all scss file of components to a *.css file.