Fixed current page ancestor menu item

reference:
http://codex.wordpress.org/Function_Reference/wp_list_pages#Current-Page_Ancestor_Menu_Items
http://codex.wordpress.org/Function_Reference/wp_nav_menu#Current-Page_Menu_Items

library/scss/breakpoints/_768up.scss

@@ -115,7 +115,7 @@ NAVIGATION STYLES
 			/* highlight sub-menu current page */
 			li.current-menu-item,
 			li.current_page_item,
-			li.current-page-ancestor {
+			li.current_page_ancestor {
 				a {}
 			}
 		}
@@ -131,7 +131,7 @@ NAVIGATION STYLES
 	/* highlight current page */
 	li.current-menu-item,
 	li.current_page_item,
-	li.current-page-ancestor {
+	li.current_page_ancestor {
 		a {}
 	}  /* end current highlighters */