Shorthand property for grid-column-start and grid-column-end.
default
grid-column: auto auto;
The grid item's column start and end are automatically set.
grid-column: 1 / 3;
The grid item starts before the first column and ends just before the third one.
grid-column: span 3;
The grid item spans 3 columns.
grid-column: 1 / span 4;
The grid items starts before the first column and spans for 4 columns, creating a new one in the process.
grid-column: main;
You can use an area name to "copy" its column start and end positions.