Add “On” state to wordpress menu

I have this code that generates a WP menu:

              <div id="menu">
  <?php $args = array(
    'depth'        => 1,
    'show_date'    => '',
    'date_format'  => get_option('date_format'),
    'child_of'     => 0,
    'exclude'      => '426, 508',
    'include'      => '',
    'title_li'     => __(''),
    'echo'         => 1,
    'authors'      => '',
    'sort_column'  => 'menu_order, post_title',
    'link_before'  => '',
    'link_after'   => '',
    'walker' => '' ); ?>
    <ul><div class="menu-button"><?php wp_list_pages( $args, 'sort_column=menu_order' ); ?></div></ul>
    </div>

I have some CSS to to the hover states of the menu items but is it possible to show an “on” state so if the user is on that actual page, the menu item is a different color?