.container{
    background-color: cornflowerblue;

    display: grid;
    grid-template-columns:repeat(5, 1fr);
    grid-template-rows:repeat(5, 1fr);
}

.container .block {
    margin: 20px;
    padding: 20px;
    background-color: white;
}

.block.block1 {
    grid-column-start: 1;
    grid-row-start: 1;
}

.block.block2 {
    grid-column-start: 5;
    grid-row-start: 5;
}

.block.block3 {
    grid-column-start: 1;
    grid-row-start: 5;
}

.block.block4 {
    grid-column-start: 5;
    grid-row-start: 1;
}

.block.block5 {
    grid-column-start: 3;
    grid-row-start: 3;
}

.block.block6 {
    grid-column-start: 2;
    grid-row-start: 2;
}

.block.block7 {
    grid-column-start: 4;
    grid-row-start: 4;
}

.block.block8 {
    grid-column-start: 4;
    grid-row-start: 2;
}

.block.block9 {
    grid-column-start: 2;
    grid-row-start: 4;
}