.lan_bg{
    width: 100%;
    height: 100%;
    background: #ffffff;
}
.landing img{
    position: relative;
    width: 100%;
    overflow: hidden;
    /* box-shadow: rgba(0, 0, 0, 0.1) 0px 4px 12px; */
}
/* @media(min-width:768px){
    .landing{
        width: 1300px;
        margin: 0 auto;
    }
} */