Simple jQuery collapsible plugin

This plugin enables showing or hiding content

by Sascha

HTML

<div class="collapsible">
  <h4 class="collapsible-header">
    First chapter
  </h4>
  <div class="collapsed-container">
    Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet.
  </div>
  <h4 class="collapsible-header">
    Second chapter
  </h4>
  <div class="collapsed-container">
    Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet. Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua. At vero eos et accusam et justo duo dolores et ea rebum. Stet clita kasd gubergren, no sea takimata sanctus est Lorem ipsum dolor sit amet.
  </div>
</div>

CSS

.collapsible-header {
  background: #3298dc;
  color: white;
  padding: 10px;
  margin: 0;
}

.collapsible-header::before {
  content: "\2192";
  width: 15px;
  display: inline-block;
}

.collapsible-header.expanded::before {
  content: "\2193";
  width: 15px;
  display: inline-block;
}

.collapsed-container {
  border: 1px solid #ccc;
  display: none;
}

.collapsed-container.expanded {
  display: block;
}

JavaScript

$.fn.collapsible = function() {
  this.find('.collapsible-header').each(function() {
    $(this).on('click', function() {      
      $($(this).next('div')).toggle('slide');
      $(this).toggleClass('expanded');
    });
  });
};

$('.collapsible').collapsible();