you probably don't want the trailing slash at the end of those unless you actually have a directory called main.html
Other than that, make sure that any images loaded on main.html either have a base href, or, are linked with the full path, i.e.
<img src="/path/to/image.jpg">
Otherwise when someone goes to
http://yourdomain.com/asdf/asdf/asdf
they'll get broken images.