Drop Down Menu

Hey guys,I need your help to make an drop to menu like this site: anime.fullfights.org,move your cursor to the anime series tab and you will see the drop down menu is big.I want to make it like that cause I also will be asking alot of pages to the tab so i want to make it look like this.Please reply thanks.If you need my site this is my link: http://www.narutomedia.tk