How to make menu items darker when hovering over?

Dear Aigars, there is a control to make darker the “on over” of the main menu? Now its so similar color, and i would like make it little more darker

many thanks

Add this code to Theme Options – Other – Custom CSS and see if it works.

#main-nav a:hover,
#main-nav ul li.current-menu-item a,
#main-nav ul li.current_page_ancestor a,
#main-nav ul li.current-menu-ancestor a,
#main-nav ul li.current_page_item a,
#main-nav ul li:hover > a {
	background: #388848;

You can also change this color if you are not satisfied with results.