.bg{background-color: #30363d;
height: 280px;
width: 100%;
margin: 0 auto;
}
.bg1{width: 1200px;
margin: 0 auto;}
 .item1{padding-top: 50px;padding-bottom: 30px;border-bottom:1px solid #494e54;color: #fff;}
 .right{float: right;}
 .item2{padding-top: 30px;padding-bottom: 30px;border-bottom:1px solid #494e54;color: #fff; text-align:center;}
 .item3{padding-top: 30px;padding-bottom: 30px;color: #fff; text-align:center;line-height: 30px;}
 .banquan{padding-top: 20px;}
 .item4{padding-top: 30px;padding-bottom: 50px;color: #000; line-height: 30px;}
 .tt{font-size: 36px;color: #000;font-weight: bold;text-align: center;padding-top: 30px;}
 .block-show {
     display: block;
     margin: 0 auto;
     position: relative;
     left: 50%;
     margin-left: -960px;