.grid { display: grid; grid-template-columns: 1fr 1fr 1fr [col-start] 1fr 1fr 1fr [col-end] 1fr 1fr 1fr; grid-template-rows: repeat(4, minmax(100px, auto)); gap: 20px; } .item { display: grid; grid-column: 2 / 7; grid-row: 2 / 4; grid-template-columns: subgrid [sub-a] [sub-b] [sub-c] [sub-d] [sub-e] [sub-f]; grid-template-rows: subgrid; } .subitem { grid-column: col-start / col-end; grid-row: 1 / 3; } .subitem2 { background-color: rgb(0 0 0 / .5); grid-column: sub-b / sub-d; grid-row: 1; }