minify WordPress theme styles.

minify-theme.php

/*-----------------------------------------------------------------------------------*/
// Register and Minify Core Stylesheets
/*-----------------------------------------------------------------------------------*/

function st_registerstyles() {
  // minify folder name (must be in your wp root).
	$minpath = '/min';

	// define directories
	$child_theme = str_replace(site_url().'/wp-content/themes/', '', get_bloginfo('stylesheet_directory'));
	$parent_theme = str_replace(site_url().'/wp-content/themes/', '', get_bloginfo('template_directory'));
	$preset_style	= of_get_option('layout_style');

    
	$minify = array(
		$parent_theme.'/css/skeleton-r.css',
		$parent_theme.'/css/formalize.css',
		$parent_theme.'/css/flexslider.css',
		$parent_theme.'/superfish.css',	
		$parent_theme.'/layout.css',
		// minify breaks when using @import so we use the parent theme version.
		// to use the child theme version, copy the styles (only the styles) into child-theme/style.css
		// make sure to leave the child theme style.css header in tact.
		$parent_theme.'/style.css',	
		$child_theme.'/'.$preset_style.'.css'
	);
	$stylesheets = join( ',', $minify );

	wp_enqueue_style('theme-styles', $wpsite.$minpath.'/b=wp-content/themes&f='.$stylesheets, NULL, NULL, NULL, 'screen, projection');
}

add_action('get_header', 'st_registerstyles');