javascript - Code Igniter add css -

although question on forum, i'd ask again. how attach css , js files in ci (code igniter framework)

here code:

views/header - <link href="<?php echo base_url(); ?>assets/css/example.css" rel="stylesheet" media="screen">

autoload.php - $autoload['helper'] = array('url');

but css doesn't work. help

put assets folder applications, system, assets

not in application , simple load url helper class in controller call header view part like

$this->load->helper('url'); $this->load->view('header'); 

and use in header file.. because $this->base_url() return / folder..

<script src="<?php echo $this->base_url();?>/assets/javascript/jquery.js"></scirpt> 

changing folder structure because access within application folder core part know..