The grid-column-start CSS property is used in grid layouts to specify the starting position of a grid item along the horizontal axis.

The grid-column-start property accepts a value that represents the grid line at which the grid item should start. Grid lines can be identified using line numbers, names of named grid lines, or the span keyword to span across multiple grid tracks.

Here’s an example:

.grid-item {
  grid-column-start: 2;

In this example, the grid-column-start: 2; rule sets the grid item to start at the second grid line horizontally. This means the grid item will begin its placement at the second grid line from the starting position of the grid container.

The grid-column-start property works in conjunction with grid-column-end to define the horizontal range of grid placement for grid items within a grid container. It provides control over the positioning and spanning of grid items in a grid layout.