<!-- BEGIN COPY / PASTE -->
    function my_custom_login_stylesheet() {
        wp_enqueue_style('custom-login', get_stylesheet_directory_uri() . '/custom-login.css');
    }
    add_action('login_enqueue_scripts', 'my_custom_login_stylesheet');

    function my_custom_login_logo_url() {
        return home_url();
    }
    add_filter('login_headerurl', 'my_custom_login_logo_url');

    function my_custom_login_logo_url_title() {
        return 'Your Site Name';
    }
    add_filter('login_headertitle', 'my_custom_login_logo_url_title');
    <!-- END COPY / PASTE -->