Add the stylelint-a11y package

.stylelintrc

@@ -1,5 +1,5 @@
 {
-    "extends": "stylelint-config-standard",
+    "extends": ["stylelint-config-standard", "stylelint-a11y/recommended"],
     "rules": {
         "indentation": 4
     }

package-lock.json

@@ -7797,6 +7797,11 @@
                 }
             }
         },
+        "stylelint-a11y": {
+            "version": "1.2.3",
+            "resolved": "https://registry.npmjs.org/stylelint-a11y/-/stylelint-a11y-1.2.3.tgz",
+            "integrity": "sha512-S/iiKFUsYBfa4suxP0pYQqoPB9R1+SnvxVuzHHlz9al0IWxLZzXlnZEqEez0zNOhVh5iO3rATUmDnbZE5wm/pQ=="
+        },
         "stylelint-config-recommended": {
             "version": "3.0.0",
             "resolved": "https://registry.npmjs.org/stylelint-config-recommended/-/stylelint-config-recommended-3.0.0.tgz",

package.json

@@ -6,7 +6,8 @@
     "license": "CC0-1.0",
     "dependencies": {
         "normalize.css": "^8.0.1",
-        "puppeteer": "^2.1.1"
+        "puppeteer": "^2.1.1",
+        "stylelint-a11y": "^1.2.3"
     },
     "devDependencies": {
         "css-loader": "^3.4.2",