Laravel - Controlar el tamaño de un bootstrap popup modal en Laravel

<!-- Begin -->

<br>

<button type="submit"  class="btn btn-primary btn-sm" data-toggle="modal"  data-backdrop="static" data-keyboard="false" data-target="#myModalHorizontal">Donate Now</button>

<!-- Modal -->

<div class="modal fade" id="myModalHorizontal" tabindex="-1" role="dialog" aria-hidden="true">

<div class="modal-dialog modal-lg">

    <div class="modal-content">

        <!-- Modal Header -->

        <div class="modal-header" style="background: #F8F8F8">

            <h4 class="modal-title" id="myModalLabel" style="color: #337AB7;">Login</h4>

            <button type="button" class="close" data-dismiss="modal" aria-label="Close"><span aria-hidden="true" class="ion-android-close"></span></button>

        </div>

      <!-- Modal Body -->

        <div class="modal-body">

			<div class="row main">

			 <div class="main-login main-center">

                          <div class="panel-title text-center">

	               		<h2 class="title">Iniciar Sesi&oacute;n</h2>

	                  </div>

					<form name="formlogin" class="form-horizontal" action="{{route('formulario.validar')}}" method="POST">

                                        @csrf

	<div class="form-group">

							<label for="name" class="cols-sm-2 control-label register">Usuario o Email</label>

							<div class="input-group mb-3">

								<div class="input-group-prepend">

									<span class="input-group-text"><i class="fa fa-user fa" aria-hidden="true"></i></span>

								</div>

									<input type="text" class="form-control" name="name" id="name" placeholder="DIGITE USUARIO O EMAIL" required autofocus/>

							</div>

						</div>

<div class="form-group">

							<label for="password" class="cols-sm-2 control-label register">Contrase&ntilde;a</label>

							<div class="input-group mb-3">

								<div class="input-group-prepend">

									<span class="input-group-text"><i class="fa fa-lock fa-lg" aria-hidden="true"></i></span>

								</div>

									<input type="password" class="form-control" name="password" id="password" placeholder="DIGITA CONTRASE&Ntilde;A" required/>

							</div>

						</div>

					        <div class="form-group ">

							<button type="submit" class="btn btn-primary btn-lg btn-block login-button">Entrar</button>

						</div>

		                        </form>

				</div>

			</div>

		</div>

            <div class="modal-body">

                <div class="modal-footer" id="modal_footer">

                </div>

            </div>

        </div>

    </div>

</div>

<!-- End -->