*{box-sizing: border-box;
margin: 0;
padding: 0;
}
main{display: grid;
    grid-template-columns: repeat(3,1fr);
    grid-template-rows: repeat(3.150px);
    border: solid darkred 8px;
    padding: 2rem;
}
section{display: grid;
    grid-template-columns: repeat(3,1fr);
    grid-template-rows: repeat(3,150px);
    border:solid orangered;
    margin: 1rem;
}

article{
    border: solid black;
    background: gray;
    height: 60px;
    width: 60px;
}