you can use this code in config.php
$ark_root = "http://".$_SERVER['HTTP_HOST'];
$ark_root .= str_replace(basename($_SERVER['SCRIPT_NAME']),"",$_SERVER['SCRIPT_NAME']);
$config['base_url'] = $ark_root;
$root = "http://".$_SERVER['HTTP_HOST'];
/*assets path*/
define('HTTP_CSS_PATH', $config['base_url'].'assets/css/');
define('HTTP_DOC_PATH', $config['base_url'].'assets/docs/');
define('HTTP_IMAGES_PATH', $config['base_url'].'assets/images/');
define('HTTP_JS_PATH', $config['base_url'].'assets/js/');
define('HTTP_IMG_PATH', $config['base_url'].'assets/img/');
you can use it local as well as on server too