*{
    padding: 0;
    margin: 0;
}
.yw-main{
    width: 100vw;
    height: 100vh;
    background: url("../img/zhuyaotu.jpg")no-repeat 50%;
    background-size: cover;
    display: flex;
    flex-direction: column;
}
.center{
    height: px;
    background: #999;
    padding-top: 20px;
}
.center p{
    text-align: center;
}
.banner{
    display: block;
    width: 100%;
    height: 500px;
    
}

.button{
    margin-top: 10px;
    width: 100%;
    height: 110px;
}
.down-left{
    display: inline-block;
    width: 45%;
    text-align: center;
}
.down-zhong{
    display: inline-block;
}
.down{
    width: 45%;
    margin: 0 auto;
    display: inline-block;
    text-align: center;
}
.down a{
    display: inline-block;
}