JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css">
<script src="http://1000hz.github.io/bootstrap-validator/dist/validator.min.js"></script>
      <div class="cabecera-modal">
        <button type="button" class="close" data-dismiss="modal"> <span aria-hidden="true">&times;</span> </button>
        <h4 class="titulo-modal-form">Contact Form</h4>
      </div>
      <div class="contenido-modal-form">
        <form id="formulario-cdb" id="form" class="form-horizontal" role="form" data-toggle="validator" data-delay="100" data-disable="false">
        <div class="form-group">
          <label  class="col-sm-2 leyenda" for="email-cdb">Email</label>
          <div class="col-sm-12">
            <div class="input-group">
              <div class="input-group-addon"> <i class="glyphicon glyphicon-envelope"></i> </div>
              <input type="email" class="form-control" id="email-cdb" placeholder="Tu e-mail" data-error="QWE" required>
              <span class="glyphicon form-control-feedback" aria-hidden="true"></span> </div>
            <span class="help-block with-errors"></span> </div>
        </div>
        <div class="form-group">
          <label  class="col-sm-2 leyenda" for="password-cdb">Password</label>
          <div class="col-sm-12">
            <div class="input-group">
              <div class="input-group-addon"> <i class="glyphicon glyphicon-lock"></i> </div>
              <input type="password" class="form-control" id="password-cdb" placeholder="Contraseña" data-error="QWE" required>
            </div>
            <span class="help-block with-errors"></span> </div>
        </div>
        <div class="form-group">
          <label  class="col-sm-2 leyenda" for="modelo-cdb">Test1</label>
          <div class="col-sm-12">
            <div class="input-group">
              <div class="input-group-addon"> <i class="glyphicon glyphicon-tag"></i> </div>
              <input type="text" class="form-control"...

CSS

.alert{
    display: none;
}

JavaScript

$(document).ready(function(){
    $('button').click(function(){
        $('.alert').show()
    }) 
});