* { 
 margin:0px; 
 padding:0px; 
}
body { 
 font-family:"微软雅黑",Arial, Helvetica, sans-serif, "宋体", "黑体"; 
 font-size:14px; 
 color:#333333;
}




.left_nav{ width:49px; height:auto;padding:5px;position:fixed; left:50%; top:50%; margin:-130px 0px 0px -670px; z-index:777; background:#436dad;  }
.left_nav dl{position:relative;}
.left_nav dl dt{}
.left_nav dl dd{ width:49px; height:80px;margin-bottom:7px; padding:3px 0;}
.left_nav dl dd .nav_right{ width:1174px; height:473px; overflow:hidden; position:absolute; left:54px; top:-5px; padding:0 20px;background:#fff; display:none; border:1px solid #436dad;margin-left:-5px;}
.left_nav dl dd a.nav_left{width:49px; height:80px; padding:3px 0; display:block; text-align:center;color:#fff;border-bottom:1px solid #fff;letter-spacing: 0.25em;}