*{
    margin: 0;
    padding: 0;
}

html,body{
    background: url('./images/bg.png') no-repeat;
    /*overflow-y: hidden;*/
    position: relative;
}



.center_logo{
    width: 670px;
    margin: 80px auto 20px;
}
.center_logo img{
    width: 100%;
}


.center{
    height: 360px;
    position: relative;
}
.center img:nth-child(1){
    position: absolute;
    top: 0px;
    left: 0px;
}
.center img:nth-child(2){
    position: absolute;
    top: 20px;
    left: 350px;
}
.center img:nth-child(3){
    position: absolute;
    top: 0;
    left: 592px;
}
.center img:nth-child(4){
    position: absolute;
    top: 20px;
    left: 834px;
}
.center img:nth-child(5){
    position: absolute;
    top: 0px;
    left: 1075px;
}
.center img:nth-child(6){
    position: absolute;
    top: 20px;
    left: 1318px;
}
.center img:nth-child(7){
    position: absolute;
    top: 0px;
    left: 1562px;
}
.xiaoxiang{
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
}

.nav{
    width: 600px;
    margin: 15px auto;
}
._nav{
    display: flex;
    text-align: center;
    justify-content: space-between;
    line-height: 50px;
    color: #fff;
    font-size: 28px;
    font-family: "Microsoft YaHei";
}
._nav div{
    width: 205px;
    height: 50px;
    background: url('./images/btn_bg.png') no-repeat;
    background-size: 100% 100%;
}
._nav div a{
    color: #fff;
    text-decoration: none;
}

.bottom{
    width: 320px;
    height: 112px;
    margin: 160px auto;
}
.bottom img{
    width: 100%;
    height: 100%;
}