[CSS] help with a orizzotal menu

hi i have this <div id="nav"><ul><li><a href="/item1.php"><em>Menu item 1</em></a><ul><li><a href="/item1.1.php">Menu item 1.1</a></li><li><a href="/item1.2.php"><em>Menu item 1.2</em></a><ul><li><a href="/item1.2.1.php">Menu item 1.2.1</a></li><li><strong>Menu item 1.2.2</strong><ul><li><a href="/item1.2.2.1.php">Menu item 1.2.2.1</a></li><li><a href="/item1.2.2.2.php">Menu item 1.2.2.2</a></li></ul></li><li><a href="/item1.2.3.php">Menu item 1.2.3</a></li></ul></li><li><a href="/item1.3.php">Menu item 1.3</a></li></ul></li><li><a href="/item2.php">Menu item 2</a></li><li><a href="/item3.php">Menu item 3</a></li><li><a href="/item4.php">Menu item 4</a></li></ul></div> i would like to add a css and/or a javascript to skin this menu as a orizzontal menu with submenu orizzontal under menu.. and subsubmenu orizzontal and under submenu.. thanks a lot