grid-gap

/* One <length> value */
grid-gap: 20px;
grid-gap: 1em;
grid-gap: 3vmin;
grid-gap: 0.5cm;

/* One <percentage> value */
grid-gap: 16%;
grid-gap: 100%;

/* Two <length> values */
grid-gap: 20px 10px;
grid-gap: 1em 0.5em;
grid-gap: 3vmin 2vmax;
grid-gap: 0.5cm 2mm;

/* One or two <percentage> values */
grid-gap: 16% 100%;
grid-gap: 21px 82%;

/* Global values */
grid-gap: inherit;
grid-gap: initial;
grid-gap: unset;

Applies to grid containers   [Inherited](inheritance) no   Media visual   [Computed value](computed_value) as each of the properties of the shorthand:

Animation type as each of the properties of the shorthand:

Canonical order the unique non-ambiguous order defined by the formal grammar  

<'grid-row-gap'> <'grid-column-gap'>?

<div id="grid">
  <div></div>
  <div></div>
  <div></div>
  <div></div>
  <div></div>
  <div></div>
  <div></div>
  <div></div>
  <div></div>
</div>

#grid {
  display: grid;
  height: 200px;
  grid-template: repeat(3, 1fr) / repeat(3, 1fr
  grid-gap: 20px 5px;
}

#grid > div {
  background-color: lime;
}