JSFiddle - React, Tailwind, and code Playground

HTML

<div class="first-div">
  <div class="second-div">
  </div>
</div>

CSS

.first-div {
    background-color: #f5f5f5;
    margin-top: 5px;
    margin-left: 5px;
    margin-right: 5px;
    border-radius: 6px;
    border: 1px solid #b8b8b8;
    text-align: justify;
    padding: 4px 4px 4px 4px;
    word-wrap: break-word;
    height: auto;
    overflow: hidden;
}
.second-div {
    background-color:red;
    width: 30%;
    float: right;
    font-size: 9px;
    min-height: 300px; /*change height */
}