How can CSS be utilized to create a navigation system in PHP?

To create a navigation system in PHP using CSS, you can create a PHP file that generates the navigation links dynamically and then use CSS to style and position the navigation elements on the webpage. This allows for easy customization and maintenance of the navigation system.

```php
<?php
$navItems = array(
    'Home' => 'index.php',
    'About' => 'about.php',
    'Services' => 'services.php',
    'Contact' => 'contact.php'
);
?>

<nav>
    <ul>
        <?php foreach ($navItems as $name => $url) : ?>
            <li><a href="<?php echo $url; ?>"><?php echo $name; ?></a></li>
        <?php endforeach; ?>
    </ul>
</nav>
```

In the above PHP code snippet, an array `$navItems` is used to store the navigation links and their corresponding URLs. The `foreach` loop is then used to iterate through the array and generate the navigation links dynamically. The navigation links are outputted within an unordered list (`<ul>`) which can be styled using CSS to create a visually appealing navigation system.