<button class="custom-nonfabl-accordion">Section 1</button>
  <div class="custom-nonfabl-accordion-panel">
    <p>Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book.</p>
  </div>
  
  <button class="custom-nonfabl-accordion">Section 2</button>
  <div class="custom-nonfabl-accordion-panel">
    <p>Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book.</p>
  </div>
  
  <button class="custom-nonfabl-accordion">Section 3</button>
  <div class="custom-nonfabl-accordion-panel">
    <p>Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book.</p>
  </div>
  
  <style>
    .custom-nonfabl-accordion {
      background-color: #eee;
      color: #444;
      cursor: pointer;
      padding: 18px;
      width: 100%;
      text-align: left;
      border: none;
      outline: none;
      transition: 0.4s;
    }
    
    .custom-nonfabl-accordion + div.custom-nonfabl-accordion-panel {
      height: 0px;
      transition: height 1s ease-out 0.2s;
    }
    
    .accordion-active,
    .custom-nonfabl-accordion:hover {
      background-color: #ccc;
    }
    
    .accordion-active + div.custom-nonfabl-accordion-panel {
      height: 60px;
    }
    
    .custom-nonfabl-accordion-panel {
      padding: 0 18px;
      background-color: white;
      display: none;
      overflow: hidden;
    }
  </style>
  
  <script>
    cb(function() {
      let accordion = document.querySelectorAll(".custom-nonfabl-accordion");
      for (let i = 0; i < accordion.length; i++) {
        accordion[i].addEventListener("click", function() {
          this.classList.toggle("accordion-active");
          let panel = this.nextElementSibling;
          if (panel.style.display === "block") {
              panel.style.display = "none";
          } else {
              panel.style.display = "block";
          }
        });
      }
    })
  </script>