What are the potential pitfalls of using outdated HTML tags like <font> in PHP code?

Using outdated HTML tags like <font> in PHP code can lead to non-standard and deprecated code, which may not render correctly in modern browsers. It is recommended to use CSS for styling instead of HTML tags like <font>. To fix this issue, you can update the code to use CSS for styling the text.

echo '<p style="font-family: Arial, sans-serif; font-size: 16px; color: #333;">This is a styled text using CSS.</p>';