not-found.html

<div class="alert alert-danger alert-dismissible" role="alert" id="notFoundWarning">
    <button type="button" class="close" data-dismiss="alert">
          <span aria-hidden="true">&times;</span>
          <span class="sr-only">Close</span>
    </button>
    <span data-text="Not_Found_Error" class="lead">
        <b>404 Error:</b> Sorry, that page doesn't exist anymore!
    </span>
</div>