JSFiddle - React, Tailwind, and code Playground

HTML

<div id="content">

	<form id="jform" action="mailer.php" method="post">

		<fieldset>

			<legend>Personal Info</legend>

			<p>

				<label for="fullname" class="block">Full Name <span>*</span> :</label>

				<input type="text" name="fullname" id="fullname" />

			</p>
			
			
			<p>

				<label for="company" class="block">Company/organisation Name:</label>

				<input type="text" name="company" id="company" />

			</p>


		</fieldset>

		

		<fieldset>

			<legend>Email</legend>

			<p>

				<label for="email" class="block">Email <span>*</span> :</label>

				<input type="email" name="email" id="email" />

			</p>
			
			<p>

				<label for="phone" class="block">Phone Number <span>*</span> :</label>

				<input type="number" name="phone" id="phone" />

			</p>

		</fieldset>

		

		<fieldset>

			<legend>Message</legend>

			<p>

				<label for="message" class="block">Message <span>*</span> :</label>

				<textarea name="message" id="message" cols="50" rows="10"></textarea>

			</p>

		</fieldset>
		
		<fieldset>

			<legend>About You</legend>

			<p>

				<label for="comment" class="block">How did you hear about us? :</label>

			  <input type="text" name="comment" id="comment" />

			</p>

		</fieldset>

		<p>

			<button type="submit" id="send">submit</button>

		</p>

	</form>

</div>

CSS

body {
	background: #efefef;
	margin: 0;
	padding: 0;
	border: none;
	text-align: center;
	font: normal 14px Georgia, "Times New Roman", Times, serif;
	color: #222;
}

#content {
	width: 500px;
	margin: 0 auto;
	margin-bottom: 25px;
	padding: 0;
	text-align: left;
}

fieldset {
	margin-top: 25px;
	padding: 15px;
	border: 1px solid #d1d1d1;
	-webkit-border-radius: 7px;
	-moz-border-radius: 7px;
	border-radius: 7px;

}

fieldset legend {
	font: normal 30px Verdana, Arial, Helvetica, sans-serif;
	text-shadow: 0 1px 1px #fff;
	letter-spacing: -1px;
	color: #273953;
}

input, textarea {
	padding: 3px;
}

label {
	cursor: pointer;
}

.block {
	display: block;
}

small {
	letter-spacing: 1px;
	font-size: 11px;
	font-style: italic;
	color: #9e9e9e;
}

.info {
	text-align: left;
	padding: 5px;
	font: normal 11px Verdana, Arial, Helvetica, sans-serif;
	color: #fff;
	position: absolute;
	display: none;
	-webkit-border-radius: 5px;
	-moz-border-radius: 5px;
	border-radius: 5px;
	-webkit-box-shadow: -1px 1px 2px #a9a9a9;
	-moz-box-shadow: -1px 1px 2px #a9a9a9;
	box-shadow: -1px 1px 2px #a9a9a9;
}

.error {
	background: #f60000;
	border: 3px solid #d50000;

}

.correct {
	background: #56d800;
	border: 3px solid #008000;
}

.wrong {
	font-weight: bold;
	color: #e90000;
}

.normal {
	font-weight: normal;
	color: #222;
}

#send {
	background: #3f5a81;
	width: 100%;
	border: 5px solid #0F1620;
	font: bold 30px Verdana, sans-serif;
	color: #fafafa;
	text-shadow: 1px 1px 1px #0F1620;
	-webkit-border-radius: 7px;
	-moz-border-radius: 7px;
	border-radius: 7px;
}

#send:hover {
	background: #4d76b1;
	border: 5px solid #253750;
	color: #fff;
}

#send:active {
	text-indent: -10px;
}

JavaScript

$(document).ready(function(){ 
// ====================================================== //

var jVal = {
	'fullName' : function() {
	
		$('body').append('<div id="nameInfo" class="info"></div>');
		
		var nameInfo = $('#nameInfo');
		var ele = $('#fullname');
		var pos = ele.offset();
		
		nameInfo.css({
			top: pos.top-3,
			left: pos.left+ele.width()+15
		});
		
		if(ele.val().length < 4) {
			jVal.errors = true;
				nameInfo.removeClass('correct').addClass('error').html('&larr; please tell us who you are').show();
				ele.removeClass('normal').addClass('wrong');				
		} else {
				nameInfo.removeClass('error').addClass('correct').html('&radic;').show();
				ele.removeClass('wrong').addClass('normal');
		}
	},
	
	'phone' : function (){
		
		$('body').append('<div id="phoneInfo" class="info"></div>');

		var phoneInfo = $('#phoneInfo');
		var ele = $('#phone');
		var pos = ele.offset();
		
		phoneInfo.css({
			top: pos.top-3,
			left: pos.left+ele.width()+15
		});
		
		var patt = /0[ -]?[1-9](?:[ -]?\d){9}\b/;
		
		if(!patt.test(ele.val())) {
			jVal.errors = true;
				phoneInfo.removeClass('correct').addClass('error').html('&larr; we need a phone number with 11 digits and that starts with 0').show();
				ele.removeClass('normal').addClass('wrong');					
		} else {
				phoneInfo.removeClass('error').addClass('correct').html('&radic;').show();
				ele.removeClass('wrong').addClass('normal');
		}	
	},
	
	
	'email' : function() {
	
		$('body').append('<div id="emailInfo" class="info"></div>');
	
		var emailInfo = $('#emailInfo');
		var ele = $('#email');
		var pos = ele.offset();
		
		emailInfo.css({
			top: pos.top-3,
			left: pos.left+ele.width()+15
		});
		
		var patt = /^.+@.+[.].{2,}$/i;
		
		if(!patt.test(ele.val())) {
			jVal.errors = true;
				emailInfo.removeClass('correct').addClass('error').html('&larr; a valid email address would be nice ([email protected])').show();
				ele.removeClass('normal').addClass('wrong');					
		} else...