Set up ESLint for code quality

.eslintrc.yml

@@ -0,0 +1,7 @@
+env:
+  browser: true
+  es2021: true
+extends: eslint:recommended
+parserOptions:
+  ecmaVersion: latest
+rules: {}

.github/workflows/lint.yml

@@ -0,0 +1,15 @@
+name: Lint
+
+on: [push, pull_request]
+
+jobs:
+  lint:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - name: Install dependencies
+        run: npm install
+      - name: Run ESLint
+        run: npx eslint .
+      - name: Run Stylelint
+        run: npx stylelint "**/*.css"