Docs: add warning callout for Yarn Berry #20564

	name: CSS (node-sass)

	on:
	push:
	branches:
	- main
	pull_request:
	workflow_dispatch:

	env:
	FORCE_COLOR: 2
	NODE: 20

	permissions:
	contents: read

	jobs:
	css:
	runs-on: ubuntu-latest

	steps:
	- name: Clone repository
	uses: actions/checkout@v4
	with:
	persist-credentials: false

	- name: Set up Node.js
	uses: actions/setup-node@v4
	with:
	node-version: "${{ env.NODE }}"

	- name: Build CSS with node-sass
	run: \|
	npx --package node-sass@latest node-sass --version
	npx --package node-sass@latest node-sass --output-style expanded --source-map true --source-map-contents true --precision 6 scss/ -o dist-sass/css/
	ls -Al dist-sass/css

	- name: Check built CSS files for Sass variables
	shell: bash
	run: \|
	SASS_VARS_FOUND=$(find "dist-sass/css/" -type f -name "*.css" -print0 \| xargs -0 --no-run-if-empty grep -F "\$" \|\| true)
	if [[ -z "$SASS_VARS_FOUND" ]]; then
	echo "All good, no Sass variables found!"
	exit 0
	else
	echo "Found $(echo "$SASS_VARS_FOUND" \| wc -l \| bc) Sass variables:"
	echo "$SASS_VARS_FOUND"
	exit 1
	fi

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