<div class="bg">
</div>
.bg {
width: 350px;
height: 450px;
border:2px solid black;
position:relative;
overflow:hidden;
}
.bg:before {
content:'';
position:absolute;
background: #2126A6;
width: 133%;
height: 150px;
border-radius:50%;
left: 50%;
transform: translate(-50%,-50%);
}
This Pen doesn't use any external CSS resources.
This Pen doesn't use any external JavaScript resources.