main{

    width : 1200px;
    height: 600px;
    display: grid;
    grid-template-rows: 1fr 1fr 1fr;
    grid-template-columns: 1fr 1fr 1fr 1fr;
    position: absolute;
    left: 0;
    right: 0;
    bottom: 0;
    top: 0;
    margin: auto;
}

main>section{
    /*border: 2px white;*/
    margin: auto;

}

main>section>img{
    margin-left: 3px;
    width: 300px;
    height: 200px;
}