.container {
    background-color: lightgrey;
    display: grid;
    grid-template-columns: repeat(3, 2fr);
    gap: 10px;
    margin-bottom: 30px;
}
/*
1. grid-row-start
2. grid-column-start
3. grid-row-end
4. grid-column-end
*/
.item1 {
    /*grid-area: 1 / 1 / 3 / 3;*/
    grid-area: 1 / 1 / span 2 / span 2;
    background-color: blue;
}
.item5 {
    /*grid-area: 3 / 2 / 5 / 4;*/
    grid-area: span 2 / span 2;
    background-color: blue;
}