<div class="box">
  <p>height: calc(50vw * 75%);をやってます</p>
</div>
.box {
  background: teal;
  width: 50vw;
  height: calc(50vw * 75%);
  
  p {
    color: white;
  }
}
View Compiled

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

This Pen doesn't use any external JavaScript resources.