Load Custom Page CSS (WordPress)

load-custom-css.php

<?php /*  
	Check if css file of slug name exists and if it does, include stylesheet for that slug.

	Place in functions.php or make it a plugin.
		
	What is this for?

	If you need to add some custom CSS for a particular page, then this script will make that possible.
	Simply create a .css file with the name of the page slug (example: about-our-company.css) and place it in the theme /css/ folder.
	This CSS file will be automatically loaded when the page is visited. 

	Note 1: The CSS file will output in the head and ideally should load after style.css.
			Try changing the priotity (10) to a higher number until it loads after style.css.

	Note 2: If you want the CSS file to load in the footer instead, then change 'wp_head' to 'wp_footer'.
    */
	add_action('wp_head', 'include_custom_css', 10);
	function include_custom_css() {
		global $post;
		$post_slug = $post->post_name;
		$filename  = get_template_directory() . '/css/' . $post_slug . '.css';

		if (file_exists($filename)) {
			echo '<link rel="stylesheet" id="' . $post_slug . '-css" href="' . get_template_directory_uri() . '/css/' . $post_slug . '.css" type="text/css" media="all" />';
		}
	}