CSS Menu - make 2 level into 3 level

I'm attaching a typical horizontal CSS menu with sub-menus, you need to add another level of sub-menus. The level 2 items should have some image displayed if they have level 3 items. See screenshot for example. You should use (expand) the existing CSS and not bypass it with some other menu mechanism. You should have prior experience with CSS menus as this isn't necessarily a simple job. Before approval you will have to put the completed menu on some test web site because it will be tested from several locations. Menu should work in major browsers, including Google Chrome. Please explain why you are qualified to complete this task (prior experience). Thanks for bidding.