.main{
    width: 90vw;
    display: flex;
    flex-direction: row;
    justify-content: space-around; 
    margin: auto
}

.pages{
    width: 100%;
    padding: 10px;
    height: 700px;
}
iframe{
    width: 100%;
    height: 34vw;;
}


@media screen and (max-width:768px){
    .main{
        flex-direction: column;
    }
    iframe{
        height: 100vw;
    }
}