If you want to expand a cell on multiple columns or rows, you can use grid-column and grid-row properties:
.el--2 {
grid-column: 1 / 5;
grid-row: 2 / 3;
}
grid-column: 1 / 5; means start at the column 1 and finish at the column 5.
If you don't want to specify the exact index of the column, you can use span (which means start at 1 and finish at 1+4):
.el--2 {
grid-column: 1 / span 4;
grid-row: 2 / 3;
}
You can also use -1, which means go from 1 to the end of the row:
.el--2 {
grid-column: 1 / -1;
grid-row: 2 / 3;
}