Upgrade dependencies

package.json

@@ -47,8 +47,8 @@
     "autoprefixer": "10.4.7",
     "broken-link-checker": "0.7.8",
     "browser-sync": "2.27.10",
-    "csso-cli": "3.0.0",
-    "fast-xml-parser": "4.0.8",
+    "csso-cli": "4.0.1",
+    "fast-xml-parser": "4.0.9",
     "glob": "8.0.3",
     "html-entities": "2.3.3",
     "jstransformer-markdown-it": "2.1.0",
@@ -62,10 +62,9 @@
     "postcss-custom-media": "8.0.2",
     "postcss-extend": "1.0.5",
     "postcss-import": "14.1.0",
-    "postcss-media-variables": "2.0.1",
     "postcss-nesting": "10.1.10",
     "pug": "3.0.2",
-    "serve": "13.0.2",
+    "serve": "14.0.1",
     "start-server-and-test": "1.14.0",
     "sync-request": "6.1.0",
     "xml-formatter": "2.6.1"

postcss.config.js

@@ -1,14 +1,10 @@
-const mediaVariables = require('postcss-media-variables')
-
 module.exports = {
   plugins: [
     require('autoprefixer'),
     require('postcss-import'),
     require('postcss-extend'),
     require('postcss-nesting'),
-    mediaVariables,
     require('postcss-custom-media'),
     require('postcss-calc'),
-    mediaVariables,
   ],
 }