How can users customize syntax highlighting in PHP forums to suit their preferences?

Users can customize syntax highlighting in PHP forums by modifying the CSS styles associated with the syntax highlighting feature. This can be done by targeting specific classes or elements in the CSS file and adjusting properties such as color, font-size, and background color to suit their preferences.

<style>
    .comment { color: green; }
    .keyword { color: blue; }
    .string { color: red; }
</style>