.gridContainer {
    width: 90vw;
    margin: auto;
    margin-top: 300px;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
    grid-template-rows: repeat(11, 100px);
    grid-auto-flow: dense;
    grid-gap: 20px;
}

.o1 {
    grid-column-end: span 1;
    grid-row-end: span 1;
    background: red;
}

.o2 {
    grid-column-end: span 2;
    grid-row: span 3;
    background: red;
}

.o3 {
    grid-column-end: span 3;
    grid-row: span 4;

    background: red;
}

.o4 {
    grid-column-end: span 4;
    grid-row-end: span 5;

    background: red;
}