function toggle_visibility(id) {
       var e = document.getElementById(id);
       if(e.style.display == 'block')
          e.style.display = 'none';
       else
          e.style.display = 'block';
    }
	
	    function toggle_menu(id) {
       var f = document.getElementById(id);
       if(f.style.backgroundImage == 'url(/tl/images/button/share_down.jpg)')
          f.style.backgroundImage = 'url(/tl/images/button/share_up.jpg)';
       else
          f.style.backgroundImage = 'url(/tl/images/button/share_down.jpg)';
    }