Форма обратной связи JS с кнопкой на CSS

<div class="container">
<form id="contactus" action="" method="post">
<h3>Форма обратной связи</h3><fieldset>  
<input placeholder="name" type="text" tabindex="1" required autofocus> </fieldset>

<fieldset> <input placeholder="Email Address" type="email" tabindex="2" required> </fieldset>
   
<fieldset> <input placeholder="Phone Number" type="tel" tabindex="3" required> </fieldset>
   
<fieldset> <textarea placeholder="Type your message here..." tabindex="5" required></textarea> </fieldset>
   
<fieldset> <button name="submit" type="submit" id="contactus-submit" data-submit="Отправка"><i id="icon" class=""></i> Отправить сейчас</button> </fieldset>
   
</form>
</div>

.container{
max-width: 400px;
width: 100%;
margin: 0 auto;
position: relative }

#contactus{
font: 400 12px/16px 'Roboto', Helvetica, Arial, sans-serif;
background: #F9F9F9;
padding: 25px;
margin: 150px 0;
box-shadow: 0 0 20px 0 rgba(0, 0, 0, 0.2), 0 5px 5px 0 rgba(0, 0, 0, 0.24) }

#contactus{
}

#contactus h3{
display: block;
font-size: 30px;
font-weight: 300;
margin-bottom: 10px }

#contactus h4{
margin: 5px 0 15px;
display: block;
font-size: 13px;
font-weight: 400 }

fieldset{
border: medium none !important;
margin: 0 0 10px;
min-width: 100%;
padding: 0;
width: 100% }

#contactus input[type='text'], #contactus input[type='email'], #contactus input[type='tel'], #contactus input[type='url'], #contactus textarea{
width: 100%;
border: 1px solid #ccc;
background: #FFF;
margin: 0 0 5px;
padding: 10px }

#contactus input[type='text']:hover, #contactus input[type='email']:hover, #contactus input[type='tel']:hover, #contactus input[type='url']:hover, #contactus textarea:hover{
-webkit-transition: border-color 0.3s ease-in-out;
-moz-transition: border-color 0.3s ease-in-out;
transition: border-color 0.3s ease-in-out;
border: 1px solid #aaa }

#contactus textarea{
height: 100px;
max-width: 100%;
resize: none }

#contactus button[type='submit']{
cursor: pointer;
width: 100%;
border: none;
background: #f0715f;
color: #FFF;
margin: 0 0 5px;
padding: 10px;
font-size: 15px }

#contactus button[type='submit']:hover{
background: #f07150;
-webkit-transition: background 0.3s ease-in-out;
-moz-transition: background 0.3s ease-in-out;
transition: background-color 0.3s ease-in-out }

#contactus button[type='submit']:active{
box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.5) }

#contactus input:focus, #contactus textarea:focus{
outline: 0;
border: 1px solid #aaa }

::-webkit-input-placeholder{
color: #888 }

:-moz-placeholder{
color: #888 }

::-moz-placeholder{
color: #888 }

:-ms-input-placeholder{
color: #888  
}

$(document).ready(function(){

$("#contactus-submit").click(function(){
var r= $('');

$("#contactus-submit").html(r);

$("#contactus-submit").append(" Sending...");

$("#contactus-submit").attr("disabled", true);
setTimeout(function(){
$("#contactus-submit").attr("disabled", false);
$("#contactus-submit").html('Send');

}, 3000);

});

});