Demetrius Pop on "CSS for plugin"

I have this simple plugin that creates a copyright in the footer section.
`function add_copyright() {
$copyright_message = "Copyright ". date(Y) . bloginfo('name') . ", All Rights Reserved";
echo '<div id="plugin-copyright">' . $copyright_message . '</div>';
}
add_action("wp_footer",add_copyright);`

My question is:
How do I add the CSS so that the div can be positioned?