JSFiddle - React, Tailwind, and code Playground

HTML

<!DOCTYPE html>
<html>

 <head>
  <script src="//code.jquery.com/jquery-1.11.2.min.js"></script>
  <script src="//code.jquery.com/jquery-migrate-1.2.1.min.js"></script>
</head> 

<body>
<form method='post' class='reg-form'>
    <div class='form-row'>
        <label for='form_fname'>First Name: </label>
        <input type='text' id='form_fname' name='first_name'>
    </div>
    <div class='form-row'>
        <label for='form_sname'>Second Name: </label>
        <input type='text' id='form_sname' name='second_name'>
    </div>
    <div class='form-row'>
        <label for='form_email'>Email: </label>
        <input type='email' id='form_email' name='email'>
    </div>
    <div class='form-row'>
        <label for='form_phone'>Phone: </label>
        <input type='text' id='form_phone' name='phone'>
    </div>
    <div class='form-row'>
        <label for='form_about'>About myself: </label>
        <textarea id='form_about' name='about'></textarea>
    </div>
    <div class="form-row">
        <input type="submit" value='Go'>
    </div>

</form>
</body>

CSS

.form-row {
	margin-bottom: 8px;
	overflow: hidden;
}
.form-row input {
	float: right;
	height: 19px;
	line-height: 19px;
	margin: 0px;
	padding: 0px 5px;
	width: 287px;
	border: 1px solid #ABADB3;
}

.reg-form {
	width: 416px;
	margin: 0 auto;
}

.form-row textarea {
	height: 90px;
    line-height: 16px;
    font-size: 12px;
    padding: 0px 5px;
    width: 404px;
    border: 1px solid #ABADB3;
}

.form-row input[type=submit] {
	padding:5px;
	height:25px;
	width:100%;
	line-height: 10px;
	background: #337AB7;
	color:white;
}

.form-row input[type=submit]:hover {
	background:#286090;
}

* {
	font-family:arial;
	font-size:10pt;
}

JavaScript

$(document).ready(function(){
            $("input[type='submit']").click(function(){
                    // find all fields, except "[type='submit']"
                var fields = $(this).parents("form").find("input, textarea").not("[type='submit']");
                var validated = true;
                for(var i = 0; i < fields.length; i++) {
                    validated = validated && (fields[i].value !== '');
                }
                if (!validated) {
                alert('Fill the fields');
                }
                return validated;
            });
        });