JSFiddle - React, Tailwind, and code Playground

HTML

<div id="contact"> 
            <form id="signup" action="<?=$_SERVER['PHP_SELF']; ?>" method="get"> 
                <fieldset>
                    <span id="response">
                        <? require_once('inc/store-address.php'); if($_GET['submit']){ echo storeAddress(); } ?>
                    </span>
                    <input type="email" name="email" id="email" placeholder="Enter your email address" /> 
                    <input type="submit" id="submit" class="btn" value="Go" />             
                </fieldset> 
            </form> 
        </div>

CSS

#contact {
    width: 140px;
    height: 95px;
    margin: 60px auto;
    /*background: #c9d0de; border: 1px solid #e1e1e1;
    -moz-box-shadow: 0px 0px 8px #444;
    -webkit-box-shadow: 0px 0px 8px #444;*/
}
#response {
    width:140px;
    height:25px;
    margin-bottom:10px;
    display:block;
    font-style:italic;
}
input {
    width: 124px;
    outline:none;
    height: 9px;
    padding: 8px;
    margin: 0 0 10px 0; 
    background: #5E768D;
    background: -moz-linear-gradient(top, #546A7F 0%, #5E768D 20%);
    background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#546A7F), color-stop(20%,#5E768D));
    border-radius: 10px;
    -moz-border-radius: 10px;
    -webkit-border-radius: 10px;
    -moz-box-shadow: 0px 1px 0px #f2f2f2;
    -webkit-box-shadow: 0px 1px 0px #f2f2f2;
    font-family: sans-serif;
    font-size: 10px;
    color: #f2f2f2;
    text-shadow: 0px -1px 0px #334f71;
}
    input::-webkit-input-placeholder  {
        color: #a1b2c3; text-shadow: 0px -1px 0px #38506b;  
    }
    input:-moz-placeholder {
        color: #a1b2c3; text-shadow: 0px -1px 0px #38506b; 
    }
input:focus, textarea:focus {
    background: #728eaa;
    background: -moz-linear-gradient(top, #668099 0%, #728eaa 20%);
    background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#668099), color-stop(20%,#728eaa));
}

input[type=submit] {
    width: 40px;
    height: 25px;
    padding:5px;
    margin: 0 auto;
    display:block;
    -moz-box-shadow: 0px 0px 5px #999;-webkit-box-shadow: 0px 0px 5px #999;
    border: 1px solid #556f8c;
    background: -moz-linear-gradient(top, #718DA9 0%, #415D79 100%);
    background: -webkit-gradient(linear, left top, left bottom, color-stop(0%,#718DA9), color-stop(100%,#415D79));
    cursor: pointer;
}