Grid Items
A grid container contains one or more grid items.
By default, a container has one grid item for each column, in each row, but you can style the grid items so that they will span multiple columns and/or rows.
The grid-column-start and grid-column-end Properties
The grid-column-start property specifies where to start a grid item.
The grid-column-end property specifies where to end a grid item.
Example
Place the first grid item at column-line 1, and let it end on column-line 3:
.item1 {
grid-column-start: 1;
grid-column-end: 3;
}