<div class="container">
<div class="item"></div>
</div>
.container {
position: relative;
display: flex;
height: 90vh;
width: 90vw;
border: 3px solid black;
margin: auto;
}
.item {
background: teal;
padding: 50px;
width: 70vw;
margin: auto;
}
This Pen doesn't use any external CSS resources.
This Pen doesn't use any external JavaScript resources.