How can PHP developers ensure consistent font sizes and colors in HTML emails?

To ensure consistent font sizes and colors in HTML emails, PHP developers can use inline styles within the HTML code. This means specifying the font size and color directly within the HTML tags, rather than relying on external CSS stylesheets. By doing this, the styles will be applied consistently across different email clients.

<?php
$font_size = "16px";
$font_color = "#333333";

$email_content = "
<html>
<head>
</head>
<body>
<p style='font-size: $font_size; color: $font_color;'>This is an example email content with consistent font size and color.</p>
</body>
</html>
";
?>