I spent a lot of time for seeking an appropriate solution to use external stylesheets in CodeIgniter. If you are not patient, I think you will give up the racing.
Here is the silver point I have found. It can be described briefly as follows:
Typically, create an “assets” directory for files that need to be accessed like the following:
Pay attention to that all file references are usually based upon the
index.php file. This means you would access a
css file via “assets/styles/mystyle.css”
You could try several instructions as follows:
<link href="<?php echo base_url().'assets/styles/style.css';?>" rel="stylesheet" type="text/css" />