What are the limitations of PHP in terms of client-side interactions like hover effects?

PHP is a server-side language, so it cannot directly handle client-side interactions like hover effects. To achieve hover effects, you would typically use a combination of HTML, CSS, and JavaScript. JavaScript is a client-side language that can handle interactions like hover effects.

// This is an example of how you can use PHP to generate HTML with CSS classes for hover effects
echo '<div class="hover-effect">Hover over me</div>';
```
```css
/* CSS for hover effect */
.hover-effect {
  background-color: blue;
  color: white;
  padding: 10px;
}

.hover-effect:hover {
  background-color: red;
}