JSFiddle - React, Tailwind, and code Playground

HTML

<div class="main-div">
  <div class="title-div">
    title
  </div>
  <div class="body-div">
    body
  </div>
</div>
<br>
<br>
<input class="btn" type="button" value="Toggle title visibility" />

CSS

.main-div {
  height: 150px;
  width: 150px;
  background-color: lightgray;
  border: 1px solid black;
}

.title-div {
  height: 25px;
  width: 100%;
  background-color: lightblue;
}

.body-div {
  height: calc(100% - 25px);
  width: 100%;
  background-color: green;
}

/* from bootstrap*/
.hidden {
  display: none !important;
  visibility: hidden !important;
}

JavaScript

$(".btn").click(function() {
	$(".title-div").toggleClass("hidden");
});