Menu Bar Current Item

I am trying to set up the Horizontal Main Menu Item to a specific color for the current item/page, but have not been able to find the code for it.

Also, the option does not seem to exist under the Theme’s Header Options where it’s supposed to be.

I know the following code would be the general syntax but this doesn’t work with this theme.

“nav[role=navigation] .menu ul li.current-menu-item a,
.nav ul li.current_page_item a,
nav[role=navigation] .menu ul li.current_page_item a {
background:#f7df2b;
box-shadow:1px 1px 0 #000;
color:#000;
}”