gap (grid-gap)

The gap CSS property sets the gaps (gutters) between rows and columns. It is a shorthand for row-gap and column-gap.

Values

<length>: Is the width of the gutter separating the grid lines.
<percentage>: Is the width of the gutter separating the grid lines, relative to the dimension of the element.

gap="1em"
gap="3vmin"
gap="0.5cm"
gap="100%"
gap="calc(20px + 10%) calc(10% - 5px)"