I'm having issues with installation of the theme itself. I've followed the 'Laravel' installation tutorial to the letter, yet my final 'npm run dev' does not seem to work.

Node version: v16.16.0
Laravel version 9.x

It seems like this tutorial version is an older version, because it states that the package.json file is located inside the demo1 folder, yet it is located in one of the parent folders (tools).
This is the error I'm getting:

ERROR in ./resources/plugins/plugins.scss
Module build failed (from ./node_modules/mini-css-extract-plugin/dist/loader.js):
ModuleBuildError: Module build failed (from ./node_modules/sass-loader/dist/cjs.js):
SassError: expected "{".
â•·
79 │ window.jQuery = window.$ = require('jquery');
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