自定义二级导航代码，兼容宽窄屏设计

<!--以下是二级导航，开始-->
<!--Copyright (c) 2018.7-9 http://www.loufree.com All rights reserved.
Author: XHM
websities: http://www.loufree.com $-->
<style type="text/css">
#nav_2 {
        margin-left:0px;
        border-bottom: 0px solid #cdcdcd; 
        border-left: 1px solid #e2d1b8; 
        border-right: 1px solid #e2d1b8; 
        border-top: none;; 
        padding:11px; 
        overflow:hidden; 
        zoom:1; 
        width:937px;
}
#nav_2 ul { float:left; padding-left:52px; border-right:1px solid #e3e3e2; font-size:14px; height:55px; margin-top:0px; color:#616161; line-height:30px;}
#nav_2 ul li { float:left; white-space:nowrap;display:block;}
#nav_2 ul li.common { margin-right:12px;_margin-right:5px;}
#nav_2 ul li a{ color:#616161; padding:2px;}
#nav_2 ul li a:hover { color:#FF6C00; background:#fefbec; border:1px solid #febf90; padding:1px;text-decoration:none;}
#nav_2 ul.civilian{ background:url(/static/image/XHM/01.gif) no-repeat 10px 0;width:144px; }
#nav_2 ul.consumption { background:url(/static/image/XHM/02.gif) no-repeat 10px 0; width:144px;}
#nav_2 ul.mode { background:url(/static/image/XHM/03.gif) no-repeat 10px 0; width:300px;}
#nav_2 ul.life { width:131px; background:url(/static/image/XHM/04.gif) no-repeat 10px 0; border-right:none;}
#nav_2 ul.life li{display:inline; }
#nav_2 ul.mode li img.new_icon{display:block; }
</style>
    <div id="nav_2">
  <ul class="civilian">