routing issue?

[eluser]Ninjabear[/eluser]
Yes this is because CI uris work as follows:

domain.com/index.php/controller/method/id

You left out the controller so you got a 404 error.

It should be /public_site/about
Or /public_site (which would give you the index method.

Just /ci uses the default controller as set in your routes file. $route['default_controller'] = "main";

Also, the css goes in the root of your install so inside the ci folder I suppose alongside the application folder in a folder called /css for example.