<!--
/*通用*/
body{font:12px Arial,Verdana,Tahoma,"宋体";}
*{padding:0px;margin:0px;}
* li{list-style:none;}
a{text-decoration:none;color:#20537A;}
a:hover{text-decoration:underline;}
.clearfix:after {
content: "\0020";
display: block;
height: 0;
clear: both;
}
.clearfix {
_zoom: 1;
}
*+html .clearfix {
overflow:auto;
}
.menu_navcc{width:970; margin:0 auto;}
.menu_nav{width:1920;height:48px;background:url(img/nav_bg.gif) repeat-x;float:left;margin-top:22px;}
↑这里设置成1920的时候，他导航右边背景平铺了，但是左边背景还是没有平铺是白的
.menu_nav .nav_content{padding-left:25px;background:url(img/nav_l_bg.gif) no-repeat;float:left;}
.menu_nav .nav_content li{width:118px;height:48px;padding-left:15px;padding-right:13px;background:url(img/nav_li_right.gif) no-repeat right center;float:left;line-height:48px;text-align:center;font-size:14px;font-weight:bold;}
.menu_nav .nav_content li a{color:#fff;width:88px;height:48px;display:block;}
.menu_nav .nav_content li.current{line-height:37px;}
.menu_nav .nav_content li em{background:url(img/bid_new.gif) no-repeat;width:35px;height:21px;display:inline-block;position:absolute;top:-20px;left:40px;}
.menu_nav .nav_content li.current a,.menu_nav .nav_content li a:hover{width:88px;height:37px;background:url(img/nav_li_current.gif) no-repeat;display:block;color:#fff;}
.menu_nav .nav_content li a:hover{background:url(img/nav_li_hover.gif) no-repeat;line-height:37px;text-decoration:none;}
.menu_nav_right{padding-right:20px;background:url(img/nav_r_bg.gif) no-repeat right top;float:right;margin-left:50px;padding-top:13px;height:23px;padding-bottom:12px;}
p{
margin-bottom:15px}
-->
</style>
</head>
<!--nav,start-->

@Ervinfour