<html lang="zh-CN"> <head> <meta http-equiv="Content-Type" content="text/html; charset=gb2312" /> <title>下拉菜单演示</title> <style type="text/css"> <!-- *{margin:0px; padding:0px;} body {font-family: arial, 宋体, serif;font-size:12px;} #nav {line-height: 24px; list-