Uses: column-gap and row-gap to separate the grid items
.grid-container {
display: inline-grid;
grid-template-columns: auto auto auto;
column-gap: 50px;
row-gap: 20px;
background-color: indianred;
padding: 10px;
}
.grid-item {
background-color: powderblue;
text-align: center;
padding: 20px;
font-size: 30px;
}
<div class="grid-container">
<div class="grid-item">1</div>
<div class="grid-item">2</div>
<div class="grid-item">3</div>
<div class="grid-item">4</div>
<div class="grid-item">5</div>
<div class="grid-item">6</div>
</div>