A Pen by Andrew Kirchmyer.

index.html

<div class="my-ellipse"></div>
Hover and notice that the ellipse is preserved with a new width and height

responsive-ellipses.markdown

responsive ellipses

A Pen by Andrew Kirchmyer on CodePen.

License.

style.css

.my-ellipse {
    height: 50px;
    width: 100px;
    border-radius: 50%;
    background-color: yellow;
}
.my-ellipse:hover {
    height: 40px;
    width: 200px;
    transition: all 2s ease-in;
}
}