What would it mean for `grid-row-start` or `grid-row-end` to have negative values?

Question

What would it mean for grid-row-start or grid-row-end to have negative values?

Answer

If a negative integer is used, the grid line count starts in reverse. For example, grid-row-start: -1; specifies the grid line at the far most right of the grid and `grid-column-start: -1;” specifies the grid line at the bottom of the grid.