[Wordpress] Combile all your CSS into a single file

combine.php

<?php

header('Content-type: text/css');
ob_start("compress");

    function compress( $minify ) 
    {
    /* remove comments */
        $minify = preg_replace( '!/\*[^*]*\*+([^/][^*]*\*+)*/!', '', $minify );

        /* remove tabs, spaces, newlines, etc. */
        $minify = str_replace( array("\r\n", "\r", "\n", "\t", '  ', '    ', '    '), '', $minify );
            
        return $minify;
    }

    /* css files for combining */
    include('base.css');
    include('style.css');
    include('another-css.css');

ob_end_flush();