What is the potential issue with including a <div> tag in PHP code and how does it affect the layout of a webpage?

Including a <div> tag directly in PHP code can cause issues with the layout of a webpage because it mixes HTML with PHP logic, leading to messy and hard-to-maintain code. To solve this issue, it's recommended to separate the HTML markup from the PHP logic by using a templating engine like Twig or by storing the HTML in a separate file and including it in the PHP code.

<?php
// Example of separating HTML markup from PHP logic using include statement

// PHP logic
$variable = "Hello, World!";

// HTML markup in a separate file (example.html)
// <div><?php echo $variable; ?></div>

// Include the HTML file in the PHP code
include 'example.html';
?>