A Grid Layout must have a parent element with the display property set to grid or inline-grid.
.grid-container { display: grid; grid-template-columns: auto auto auto; background-color: indianred; } .grid-item { background-color: powderblue; text-align: center; margin: 10px; 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>