<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<title>简洁实用的二级下拉导航菜单</title>
<meta http-equiv="content-type" content="text/htmlcharset=gb2312">
<!--把下面代码加到<head>与</head>之间-->
<style type="text/css">
body,html{padding:0margin:0text-align:centerfont:normal 14px 'arial'}
#mainNavBar{width:100%background:#999padding:10px 0}
#nav{width:760pxheight:30pxmargin:0 auto}
#nav ul{padding:0margin:0}
#nav ul li{position:relativefloat:leftwidth:60pxheight:30pxline-height:30pxoverflow:hiddenlist-style-type:none}
#nav ul li a{display:blockcolor:#ffftext-decoration:none}
#nav ul li a:hover{font-weight:boldbackground:#666}
#subNav{position:absolutewidth:150pxtop:30pxleft:0pxpadding:5pxbackground:#666color:#ffftext-align:left}
#subNav a{text-decoration:nonefont-weight:normaldisplay:block}
#subNav a:hover{color:#f00background:#f00}
</style>
</head>
<body>
<!--把下面代码加到<body>与</body>之间-->
<div id="mainNavBar">
<div id="nav">
<ul>
<li>
<a href="#">Add</a>
<div id="subNav">
<a href="#">写日志</a>
<a href="#">增加分类</a>
</div>
</li>
<li>
<a href="#">Edit</a>
<div id="subNav">
<a href="#">修改分类</a>
<a href="#">文章编辑</a>
</div>
</li>
<li>
<a href="#">Admin</a>
<div id="subNav">
<a href="#">文章管理</a>
<a href="#">评论管理</a>
<a href="#">留言管理</a>
<a href="#">退出</a>
</div>
</li>
</ul>
</div>
</div>
<script language="javascript">
var nav=document.getElementById("nav").getElementsByTagName("li")
for(i=0i<nav.lengthi++){
nav[i].onmouseover=function(){
this.style.fontWeight="bold"
this.style.overflow="visible"
this.style.background="#666666"
}
nav[i].onmouseout=function(){
this.style.fontWeight="normal"
this.style.background="#999999"
this.style.overflow="hidden"
}
}
</script>
</body>
</html>
#header #shousuo{
width:950px
height:50px
background:#f4f4f4
margin-top:10px
}
#shousuo ul li{
line-height:50px
list-style-type:none
float:left
margin-left:5px
font-weight:bold
font-size:14px
标题可伸缩说明width属性不是具体的值而是百分比,背景如果是纯色不受影响,背景如果是图片,图片的width必须设为百分比,代码如下:
1、背景是颜色
<h1 style="width:100%background-color:#FFFFFF">这是标题1</h1>2、背景是图片
<h1 style="width:100%background-image:url(图片路径)background-size:100% 100%background-repeat:no-repeat">这是标题1</h1>属性用于调整主轴上伸缩的位置。可能的值为:flex-start (默认)
flex-end
center
space-between
space-around
这里我们设置justify-content为center
align-items 侧轴对齐
align-items是一个和justify-content相呼应的属性。align-items
......