JSFiddle - React, Tailwind, and code Playground

HTML

<div class="parent">
  <div class="child">
    'Despite growth of the Internet over the past seven years,' +
  ' the use of toll-free phone numbers in television advertising continues to grow,' +
  ' indicating that the telephone remains a prevalent response tool, according to a recent study.' +
  'Despite growth of the Internet over the past seven years,' +
  ' the use of toll-free phone numbers in television advertising continues to grow,' +
  ' indicating that the telephone remains a prevalent response tool, according to a recent study.' +
  'Despite growth of the Internet over the past seven years,' +
  ' the use of toll-free phone numbers in television advertising continues to grow,' +
  ' indicating that the telephone remains a prevalent response tool, according to a recent study.' +
  'Despite growth of the Internet over the past seven years,' +
  ' the use of toll-free phone numbers in television advertising continues to grow,' +
  ' indicating that the telephone remains a prevalent response tool, according to a recent study.' +
  'Despite growth of the Internet over the past seven years,' +
  ' the use of toll-free phone numbers in television advertising continues to grow,' +
  ' indicating that the telephone remains a prevalent response tool, according to a recent study.' +
  'Despite growth of the Internet over the past seven years,' +
  ' the use of toll-free phone numbers in television advertising continues to grow,' +
  ' indicating that the telephone remains a prevalent response tool, according to a recent study.' +
  'Despite growth of the Internet over the past seven years,' +
  ' the use of toll-free phone numbers in television advertising continues to grow,' +
  ' indicating that the telephone remains a prevalent response tool, according to a recent study.' +
  'Despite growth of the Internet over the past seven years,' +
  ' the use of toll-free phone numbers in television advertising continues to grow,' +
  ' indicating that the telephone...

CSS

body, html {
  width: 100%;
  height: 100%;
}
.parent {
  width: 400px;
  background: green;
}

.child {
  max-height: 40vh;
  background: blue;
  overflow-y: scroll;
}