The hypothetical horizontal and vertical lines that create the grid are referred to as lines. These lines are numbered starting with 1 at the top left corner of the grid and move right for columns and down for rows, counting upward.
column lines
1
2
3
4
row lines
1
2
3
4
To control the number of columns an item will consume, use the grid-column property in conjunction with the line numbers to start and end at.