.nav ul{
    width: 1070px;
    margin: 0 auto;}
.nav li{
    float: left;
    height: 46px;
    line-height: 46px;
    text-align: center;
    width: 150px;}
.nav li a {
    font-size: 17px;
    height: 46px;
    display: block;
    position: relative;
    color: #fff;}
.nav li a :link{ text-decoration:none;}
  text-decoration
.nav li a:hover, #nav li.active {
    background: #1b64a9;
    color: #fff;}
.nav li:hover {
    background: #1b64a9;}
.nav li:hover .a{
    display:block;}
.nav li .a {
    top: 46px;
    left: 0;
    width: 150px;
    display:none;
    background: #fff;
    transition: All 0.4s ease-in-out;
    -webkit-transition: All 0.4s ease-in-out;
    -moz-transition: All 0.4s ease-in-out;
    -o-transition: All 0.4s ease-in-out;}
.nav li .a .a_block{
    width:149px;
    margin:0 auto;}
.nav li .a .a_block dl{
    width:680px;
    float:left;}
.nav li .a .a_block dt{
    width:370px;
    height:130px;
    overflow:hidden;
    float:left;}
.nav li .a .a_block dd{
    width:310px;
    float:left;
    text-align:center;
    line-height:24px;}
.nav li .a .a_block dd p{
    padding-bottom:24px;
    color:#1b64a9;}
.nav li .a .a_block_ul{
    width:170px;
    float:left;}
.nav li .a .a_block_ul li{
    line-height:46px;
    text-align:center;
    overflow:hidden;
    height:46px;}
.nav li .a .a_block_ul li a{
    font-size:17px;
    color:#333;}
.nav li .a .a_block_ul li a:hover{
    color:#fff;}

.nav li a  .a_block_ul li{width:129px;}