content: Update PostCSS examples

- Remove the admonition for Windows users regarding project paths with
  spaces. The problem (gohugoio/hugo#7333) was
  resolved in v0.161.0 with commit a54c398b93821865547a9e21c73aad8a1d7f7bc1.
- Update the autoprefixer example
- Update the purgecss example

Author: jmooring

content/en/functions/css/PostCSS.md

@@ -34,17 +34,16 @@ Step 2
 Step 3
 : Create a PostCSS configuration file in the root of your project.
 
-  ```js {file="postcss.config.js"}
-  module.exports = {
+  ```js {file="postcss.config.mjs" copy=true}
+  import autoprefixer from 'autoprefixer';
+
+  export default {
     plugins: [
-      require('autoprefixer')
+      autoprefixer
     ]
   };
   ```
 
-  > [!note]
-  > If you are a Windows user, and the path to your project contains a space, you must place the PostCSS configuration within the package.json file. See [this example] and issue [#7333].
-
 Step 4
 : Place your CSS file within the `assets/css` directory.
 
@@ -107,16 +106,15 @@ To avoid using a PostCSS configuration file, you can specify a minimal configura
 
 The current Hugo environment name (set by `--environment` or in configuration or OS environment) is available in the Node context, which allows constructs like this:
 
-```js
-const autoprefixer = require('autoprefixer');
-module.exports = {
+```js {file="postcss.config.mjs" copy=true}
+import autoprefixer from 'autoprefixer';
+
+export default {
   plugins: [
     process.env.HUGO_ENVIRONMENT !== 'development' ? autoprefixer : null
   ]
-}
+};
 ```
 
-[#7333]: https://github.com/gohugoio/hugo/issues/7333
 [Node.js]: https://nodejs.org/en
 [PostCSS plugins]: https://postcss.org/docs/postcss-plugins
-[this example]: https://github.com/postcss/postcss-load-config#packagejson

content/en/functions/resources/PostProcess.md

@@ -44,9 +44,9 @@ Step 3
 Step 4
 : Create a PostCSS configuration file in the root of your project.
 
-  ```js {file="postcss.config.js" copy=true}
-  const autoprefixer = require('autoprefixer');
-  const purgeCSSPlugin = require('@fullhuman/postcss-purgecss').default;
+  ```js {file="postcss.config.mjs" copy=true}
+  import autoprefixer from 'autoprefixer';
+  import purgeCSSPlugin from '@fullhuman/postcss-purgecss';
 
   const purgecss = purgeCSSPlugin({
     content: ['./hugo_stats.json'],
@@ -62,17 +62,14 @@ Step 4
     safelist: []
   });
 
-  module.exports = {
+  export default {
     plugins: [
       process.env.HUGO_ENVIRONMENT !== 'development' ? purgecss : null,
       autoprefixer,
     ]
   };
   ```
 
-  > [!note]
-  > If you are a Windows user, and the path to your project contains a space, you must place the PostCSS configuration within the package.json file. See [this example] and issue [#7333].
-
 Step 5
 : Place your CSS file within the `assets/css` directory.
 
@@ -136,7 +133,6 @@ You cannot manipulate the values returned from the resource's methods. For examp
 {{ $css.RelPermalink | strings.ToUpper }}
 ```
 
-[#7333]: https://github.com/gohugoio/hugo/issues/7333
 [`config/production`]: /configuration/introduction/#configuration-directory
 [Autoprefixer]: https://github.com/postcss/autoprefixer
 [configure build]: /configuration/build/
@@ -145,4 +141,3 @@ You cannot manipulate the values returned from the resource's methods. For examp
 [Node.js]: https://nodejs.org/en
 [PostCSS]: https://postcss.org/
 [PurgeCSS]: https://github.com/FullHuman/purgecss
-[this example]: https://github.com/postcss/postcss-load-config#packagejson