JSFiddle - React, Tailwind, and code Playground

HTML

<div class="container">
  <div class="head">
    This is a header.
  </div>
  <div class="content">
    This is some content.<br/>
    This is some content.<br/>
    This is some content.<br/>
    This is some content.<br/>
    This is some content.<br/>
    This is some content.<br/>
    This is some content.<br/>
    This is some content.<br/>
    This is some content.<br/>
    This is some content.<br/>
    This is some content.<br/>
    This is some content.<br/>
    This is some content.<br/>
    This is some content.<br/>
    This is some content.<br/>
    This is some content.<br/>
  </div>
  <div class="foot">
    This is a footer.
  </div>
</div>

CSS

html, body {
  width: 100%;
  height: 100%;
}
body {
  display: flex;
  margin: 0;
  padding: 0;
}
.container {
  display: flex;
  flex: auto;
  flex-direction: column;
  height: 100%;
}
.head {
  background: #ccf;
}
.content {
  overflow-y: auto;
  background: #ffc;
}
.foot {
  background: #cfc;
}