CSS grid brought us the fr unit. 1fr or one fraction of the space is kind of like setting it to auto. However with fr units you can set multiple column widths and do more complex ratios e.g. grid-column-template: 1fr 3fr 1fr 2fr which would split up the area into four columns with the first and third being the same size, the fourth being twice the width of the first and third, and the second column being three times the width of the first and third.