JSFiddle - React, Tailwind, and code Playground
HTML
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>Untitled Document</title>
</head>
<body>
<div class="one_half center first column">
<h2><span>INITIAL SET-UP</span></h2>
<p class="intro_price">One off payment including first years access. </p>
<h1><span><s> £598*</s> £299* </span></h1>
<br/>
<ul><li>
<span><a href="#" class="purchase">Buy Now</a></span></li></ul><br/>
</div>
</body>
</html>
CSS
.purchase {
margin-top: 5px;
display: block;
width: 80px;
height:30px;
line-height:30px;
text-align:center;
color:white;
background: #19d7e3; /* Old browsers */
background: -moz-linear-gradient(top, #19d7e3 0%, #12a4b3 100%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%, #19d7e3), color-stop(100%, #12a4b3)); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(top, #19d7e3 0%, #12a4b3 100%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(top, #19d7e3 0%, #12a4b3 100%); /* Opera 11.10+ */
background: -ms-linear-gradient(top, #19d7e3 0%, #12a4b3 100%); /* IE10+ */
background: linear-gradient(top, #19d7e3 0%, #12a4b3 100%); /* W3C */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#19d7e3', endColorstr='#12A4B3', GradientType=0 ); /* IE6-9 */
}
.purchase:hover {
background: #12a4b3; /* Old browsers */
background: -moz-linear-gradient(top, #12a4b3 0%, #19d7e3 100%); /* FF3.6+ */
background: -webkit-gradient(linear, left top, left bottom, color-stop(0%, #12a4b3), color-stop(100%, #19d7e3)); /* Chrome,Safari4+ */
background: -webkit-linear-gradient(top, #12a4b3 0%, #19d7e3 100%); /* Chrome10+,Safari5.1+ */
background: -o-linear-gradient(top, #12a4b3 0%, #19d7e3 100%); /* Opera 11.10+ */
background: -ms-linear-gradient(top, #12a4b3 0%, #19d7e3 100%); /* IE10+ */
background: linear-gradient(top, #12a4b3 0%, #19d7e3 100%); /* W3C */
filter: progid:DXImageTransform.Microsoft.gradient( startColorstr='#12a4b3', endColorstr='#19d7e3', GradientType=0 ); /* IE6-9 */
color: #ffffff;
}