<div class="grid-container">
<div>1</div>
<div>2</div>
<div>3</div>
<div>4</div>
<div>5</div>
<div>6</div>
<div>7</div>
<div>8</div>
<div>9</div>
</div>
.grid-container{
display: grid;
grid-template-columns: 100px 100px 100px;
grid-template-rows: 100px 100px 100px;
height: 100%;
background: #d4d4d4;
grid-gap: 10px 20px;
}
.grid-container > div {
border: 1px grey solid;
}
html,body{
height: 100%;
width: 100%;
}