Forms are using Bootstrap 4 classes?

[mmoravcik]

Bootstrap 4 docs say to use a form-group https://getbootstrap.com/docs/4.6/components/forms/ e.g

  <div class="form-group">
    <label for="exampleInputEmail1">Email address</label>
    <input type="email" class="form-control" id="exampleInputEmail1" aria-describedby="emailHelp">
  </div>

And bootstrap 5 mb3 e.g https://getbootstrap.com/docs/5.0/forms/form-control/

<div class="mb-3">
  <label for="exampleFormControlInput1" class="form-label">Email address</label>
  <input type="email" class="form-control" id="exampleFormControlInput1" placeholder="name@example.com">
</div>

Although purple states bootstrap 5, it seems like it is using bootstrap 4 style forms