Block auto height like width

by Andrey Izman

HTML

<div id="container"><img src="http://via.placeholder.com/200"></div>
text after

SCSS

#container {
  background-color: red;
  display: block;
  height: 0;
  padding-bottom: 50%;
  width: 50%;
  border-radius: 50%;
  border: 2px solid green;

  img {
    border-radius: 50%;
    width: 100%;
  }

  &:after {
    content: '';
    clear: both;
    display: block;
    height: 2px;
    background: blue;
    width: 100%;
  }
}