Text Decoration for active menu page

Hi,

I want the active page in the menu to be underlined but can’t seem to achieve it. I’ve added the unlined text-decoration for hovering over the menu items using:

.omega-nav-menu li:hover {
	position: static;
	text-decoration: underline;
}

I’ve tried everything I can think of to get :active but I just can’t get it ??

site can be viewed at https://wh.thinkdigital.ie/

any ideas?