Neat (or not, depending on your position) thing about grids is that they allow for zero-size areas.

With your approach you need 4 rows with the size of 50px/4=12.5px:

`grid-template-rows: repeat(4, 12.5px) 1fr;`

However, you can also "size" first (or any other "nice" number) of rows and insert zero-sized fluff areas:

`grid-template-rows: 50px repeat(3, 0px) 1fr;`