<div class="App">
  App
  <div class="Box">
    <div class="Box-1">
      Box-1
    </div>
  </div>
</div>
.App {
  font-family: sans-serif;
  text-align: center;
  height: 400px;
  background-color: red;
  overflow: auto;
}

.Box {
  height: 600px;
  width: 200px;
  overflow: auto;
  background-color: yellow;
}

.Box-1 {
    height: 1200px;
}

External CSS

This Pen doesn't use any external CSS resources.

External JavaScript

This Pen doesn't use any external JavaScript resources.