Bootstrap Collapse
<!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"> <meta name="viewport" content="width=device-width, initial-scale=1"> <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/css/bootstrap.min.css" rel="stylesheet"> </head> <body> <button class="btn btn-primary" type="button" data-bs-toggle="collapse" data-bs-target="#moreInfo" aria-expanded="false" aria-controls="moreInfo"> Toggle details </button> <div class="collapse" id="moreInfo"> <div class="card card-body"> Here is some content that appears and disappears with a smooth animation. </div> </div> <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/js/bootstrap.bundle.min.js"></script> </body> </html>