madeas

.custom-css-textarea {  
  width: 100%;
  min-height: 150px;
  box-sizing: border-box;
  /* box-sizing: padding-box; */
  overflow:hidden;
  /* stylization */
  padding:5px;  
}

madeas

/*!	
* alignment.min.css - https://gist.github.com/madeas/99085531e003d0fa02152f03f7b9df0d
* Version - 1.0.3
* Licensed under the MIT license - http://opensource.org/licenses/MIT
*
* Copyright (c) 2018 Andrej Sharapov
*
* Normalizing styles have been helped along thanks to the fine work of
* Andrej Sharapov https://madeas.ru/
*/

madeas

<!-- jsfiddle-layouts.css -->
<div class="rec">
  <em>Recommended layout</em>
  <div class="layout">
    <label>
        <input name="editor_mode" type="radio" value="grid_4">
        <span class="gridMode grid_4"></span>
        Right results
    </label>
  </div>

madeas

<!-- jsfiddle-layouts.css -->
<div class="rec">
    <em>Recommended layout</em>
    <div class="layout">
      <label>
        <input name="editor_mode" type="radio" value="grid_1">
        <span class="gridMode active grid_1"></span>
        Classic
      </label>
    </div>

madeas

<!-- jsfiddle-layouts.css -->
<div class="rec invers">
  <em>Recommended layout</em>
  <div class="layout">
    <label>
        <input name="editor_mode" type="radio" value="grid_4">
        <span class="gridMode grid_4"></span>
        Right results
    </label>
  </div>

madeas

	<form id="form5" method="POST" action="feedback.php">
  		<div class="form-row">
   		 <div class="col">
     		 <input type="text" class="name form-control" name="name" required="required" placeholder="Представьтесь, пожалуйста" x-autocompletetype="name">
   		 </div>
 		</div>
          <div class="form-group">
            <label for="recipient-mail" class="col-form-label">Ваш email:</label>
            <input type="text" name="email" class="email form-control" id="recipient-mail" required="required" placeholder="example@mail.ru" x-autocompletetype="email">
          </div>

madeas

<form>
  <div class="form-row">
    <div class="col">
      <input type="text" name="name" class="form-control" placeholder="Представьтесь, пожалуйста">
    </div>
  </div>
    <div class="form-group">
        <label for="recipient-mail" class="col-form-label">Ваш email:</label>
        <input type="email" name="email" id="recipient-mail" class="form-control" placeholder="example@mail.ru">
    </div>

madeas

<form id="form1">
  <div class="form-row">
    <div class="col">
    <input type="hidden" name="formData" value="Заголовок формы">
      <input type="text" name="name" class="name form-control" placeholder="Представьтесь, пожалуйста">
    </div>
  </div>
    <div class="form-group">
        <label for="recipient-mail" class="col-form-label">Ваш email:</label>
        <input type="text" name="email" id="recipient-mail" class="email form-control" placeholder="example@mail.ru">

madeas

<script>
    $(document).ready(function () {
        $('form').submit(function () {
            var formID = $(this).attr('id'); // Получение ID формы
            var formNm = $('#' + formID);
            $.ajax({
                type: 'POST',
                url: 'feedback.php', // Обработчик формы отправки
                data: formNm.serialize(),
                success: function (data) {

madeas

<form id="form1" method="POST">
  <div class="form-row">
    <div class="col">
    <input type="hidden" name="formData" value="Заголовок формы">
      <input type="text" name="name" class="name form-control" placeholder="Представьтесь, пожалуйста">
    </div>
  </div>
    <div class="form-group">
        <label for="recipient-mail" class="col-form-label">Ваш email:</label>
        <input type="text" name="email" id="recipient-mail" class="email form-control" placeholder="example@mail.ru">