Is a stupid problem, but is a problem!

[eluser]jem88[/eluser]
Hi, I'm a codeigniter's newbie, and, like the title, i've a stupid trouble. I can't link to the stylesheet, but only put the <style> tag into the code. How can I take the external css? I try with
<link rel="stylesheet" type="text/css" href="<?base_url();?> framework/application/css/style.css" media="screen, print" />
thanks!!