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HTML

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Insecure Resource

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CSS

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CSS Base

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JavaScript

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JavaScript preprocessors can help make authoring JavaScript easier and more convenient.

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Babel includes JSX processing.

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Packages

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HTML 

              
                <div class="container">
  <div id="expander" class="content">
    <h2>This is a Title Here</h2>
    <p>Lorem ipsum dolor sit amet consectetur, adipisicing elit. Dolores, ducimus non alias pariatur reiciendis asperiores magnam similique deserunt natus repellendus porro! Distinctio magnam saepe expedita aliquam. Qui error culpa, quis alias maiores aut, enim nemo omnis harum repudiandae accusantium eaque, laudantium quasi praesentium autem doloribus libero velit vero magni natus minus eveniet voluptas? Ad accusantium maiores minima non necessitatibus alias maxime aut voluptatum optio dolor, perferendis blanditiis assumenda suscipit dignissimos est dolore aliquid. Repellendus assumenda non ratione itaque atque aspernatur ad amet aperiam quisquam, quia veniam cumque ducimus hic dolorem id fugit iure voluptatum quae minus reiciendis adipisci repudiandae odit, aliquid nihil! Quod sequi velit, molestias, maiores cumque architecto repellendus pariatur at corrupti expedita placeat iste ut, rerum saepe tenetur modi. Non in quo ipsa porro nam a et exercitationem minima beatae sapiente neque, ipsam quidem vitae, ut distinctio voluptate earum enim quia dicta quaerat illum deserunt. Error suscipit optio assumenda cumque ad corrupti, facilis dolores quis deserunt culpa vel esse. Eum cupiditate error sunt aliquam velit corporis molestias, id dignissimos officia nostrum debitis vero quaerat odit amet excepturi deserunt maiores delectus nobis nemo reiciendis! Quisquam facilis nostrum neque reiciendis laudantium necessitatibus ipsa enim tempora accusamus, pariatur sed iure aliquam.</p>
    <footer>
      <button onclick="toggle()" id="toggler">Show More</button>
    </footer>
  </div>
</div>
!

CSS 

              
                .content {
  display: grid;
  grid-column: 1 / -1;
  grid-row: 1 / -1;
  grid-template-rows: min-content 0fr min-content;
  transition: grid-template-rows 0.5s;
}

.expanded {
  grid-template-rows: min-content 1fr min-content;
}






















/* Base Styles */
html {
  background: #e6e7e8;
}

body {
  margin: 0;
  font-family: arial, sans-serif;
}

p {
  line-height: 1.5;
  overflow: hidden;
}

h2 {
  border-bottom: solid 1px #ccc;
  font-size: 200%;
  margin: 0;
  padding-bottom: 0.5em;
  text-align: center;
}

footer {
  margin: 0 0 1em;
  text-align: center;
}

button {
  background: #ff495d;
  border: none;
  border-radius: 0.25em;
  color: white;
  font-size: 110%;
  padding: 0.75em 1.125em;  
}

button:hover {
  background: #fcb900;
}

.container {
  display: grid;
  grid-template-rows: 3em 12em auto;
  padding: 2em 0;
}

.container::before {
  background: #3dc0d1;
  content: '';
  display: block;
  grid-column: 1 / -1;
  grid-row: 2;
}

.content {
  background: white;
  border-radius: 0.5em;
  filter: drop-shadow(0 0 0.5rem rgba(0, 0, 0, 0.3));
  margin: 0 auto;
  min-height: 14em;
  padding: 3em 1.75em 0.75em;
  transform-origin: top center;
  width: 70%;
}
!

JS 

              
                let isExpanded = false;
const expander = document.getElementById('expander');
const toggler = document.getElementById('toggler');
const toggle = () => {
  isExpanded = !isExpanded;
  expander.classList.toggle('expanded');
  toggler.innerText = isExpanded ? 'Show Less' : 'Show More';
}
!
999px

Console