The Rails asset pipeline has SCSS glob imports. Why isn't this possible everywhere? I made it possible with Broccoli.js.
// web/static/css/admin.scss
@import "admin/variables";
@import "shared/**/*";
@import "admin/**/*";
// web/static/css/app.scss
@import "app/variables";
@import "shared/**/*";
@import "app/**/*";
var mergeTrees = require('broccoli-merge-trees');
var scssGlobber = require('./scss-globber');
// Compile admin.scss and app.scss to admin.css and app.css
var cssFiles = ['admin', 'app'];
var styles = scssGlobber('web/static/css', cssFiles);
module.exports = mergeTrees([styles]);