How can I make Bootstrap alert appear on top of other elements?

I have an input box that if the value is not valid on button click should send out a bootstrap alert. I want the alert to appear on top of the input box.

Right now, it is showing below the input box. Is there a way to make it appear in the middle of the page on top of the text box?

<!-- begin snippet: js hide: false console: true babel: false -->

<!-- language: lang-js -->

const btn = document.getElementById("mybtn");
btn.addEventListener("click", () => {
  document.getElementById("show-alert").classList.remove("d-none")
});

<!-- language: lang-html -->

<link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/css/bootstrap.min.css" rel="stylesheet"/>
<script src="https://cdn.jsdelivr.net/npm/@popperjs/core@2.11.8/dist/umd/popper.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/js/bootstrap.min.js"></script>

<div class="d-flex align-items-center justify-content-center" id="record">
    <div class="input-group mb-3 input-group-lg w-50">
      <input type="text" class="form-control" id="rec-id" placeholder="Enter ID">
      <button class="btn btn-success" id="mybtn" type="button">Enter</button>
    </div>
</div>

<div class="d-flex align-items-center justify-content-center d-none" id="show-alert">
    <div class="alert alert-danger alert-dismissible fade show row">
      <button type="button" class="btn-close" data-bs-dismiss="alert"></button>
      <strong>Danger!</strong> Button was clicked
    </div>
  </div>

<!-- end snippet -->

Also on closing the alert box, is there a way to add the d-none class back?

Seems like you want a vertically centered modal. It would probably give you a better, more accessible UX.

If you do want an alert, Bootstrap provides methods for showing them. Always try to work with a library, not alongside it, to reduce effort. That's also how you'd make it reusable.

To answer the question as asked, use positioning classes. I used position-fixed to set the alert with respect to the viewport instead of a parent element, and centering is done with top-50 start-50 translate-middle.

<!-- begin snippet: js hide: false console: true babel: false -->

<!-- language: lang-js -->

const btn = document.getElementById("mybtn");
btn.addEventListener("click", () => {
  document.getElementById("show-alert").classList.remove("d-none")
});

<!-- language: lang-html -->

<link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/css/bootstrap.min.css" rel="stylesheet" />
<script src="https://cdn.jsdelivr.net/npm/@popperjs/core@2.11.8/dist/umd/popper.min.js"></script>
<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.0/dist/js/bootstrap.min.js"></script>

<div class="d-flex align-items-center justify-content-center" id="record">
  <div class="input-group mb-3 input-group-lg w-50">
    <input type="text" class="form-control" id="rec-id" placeholder="Enter ID">
    <button class="btn btn-success" id="mybtn" type="button">Enter</button>
  </div>
</div>

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<div class="position-fixed top-50 start-50 translate-middle d-flex align-items-center justify-content-center d-none" id="show-alert">
  <div class="alert alert-danger alert-dismissible fade show row">
    <button type="button" class="btn-close" data-bs-dismiss="alert"></button>
    <strong>Danger!</strong> Button was clicked
  </div>
</div>

<!-- end snippet -->