步骤如下：ul li:nth-child(2n)；ul li:nth-child(2n+1)
CSS部分:
.list {width:500pxmargin:0 auto}
.list ul {background:url(http://www.bluebirdsky.cn/images/upfiles/row_bg.gif)}
.list li {height:25pxline-height:25pxtext-align:leftpadding-left:10px}
Demo演示
<!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>
<meta http-equiv="Content-Type" content="text/htmlcharset=gb2312" />
<meta name="Author" content="青鸟" />
<meat name="Author BlogURL" content="http://www.bluebirdsky.cn/［Bluebirdsky］"
步骤如下：ul li:nth-child(2n)；ul li:nth-child(2n+1)
CSS部分:
.list {width:500pxmargin:0 auto}
.list ul {background:url(http://www.bluebirdsky.cn/images/upfiles/row_bg.gif)}
.list li {height:25pxline-height:25pxtext-align:leftpadding-left:10px}
Demo演示
<!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>
<meta http-equiv="Content-Type" content="text/htmlcharset=gb2312" />
<meta name="Author" content="青鸟" />
<meat name="Author BlogURL" content="http://www.bluebirdsky.cn/［Bluebirdsky］"
ul.dropdown:hover li {display: block
background-color: green
}
/* 用上面这个代码覆盖你的那个代码就可以了 */
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