JavaScript实现简单的二级导航菜单实例

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<title>css菜单演示</title>
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<!--
*{margin:0;padding:0;border:0;}
body {
font-family: arial, 宋体, serif;
     font-size:12px;
}
#nav {
  line-height: 24px; list-style-type: none; background:#666;
}
#nav a {
display: block; width: 80px; text-align:center;
}
#nav a:link  {
color:#666; text-decoration:none;
}
#nav a:visited  {
color:#666;text-decoration:none;
}
#nav a:hover  {
color:#FFF;text-decoration:none;font-weight:bold;
}
#nav li {
float: left; width: 80px; background:#CCC;
}
#nav li a:hover{
background:#999;
}
#nav li ul {
line-height: 27px; list-style-type: none;text-align:left;
left: -999em; width: 180px; position: absolute;
}
#nav li ul li{
float: left; width: 180px;
background: #F6F6F6;
}
#nav li ul a{
display: block; width: 180px;width: 156px;
text-align:left;padding-left:24px;
}
#nav li ul a:link  {
color:#666; text-decoration:none;
}
#nav li ul a:visited  {
color:#666;text-decoration:none;
}
#nav li ul a:hover  {
color:#F3F3F3;text-decoration:none;font-weight:normal;
background:#C00;
}
#nav li:hover ul {
left: auto;
}
#nav li.sfhover ul {
left: auto;
}
#content {
clear: left;
}
-->
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