Just an example:
<style type="text/css" media="screen">
body { font: 14px/20px Arial, Verdana, sans-serif; }
h3 { font-weight: normal; margin: 0; padding: 0; font-size: 20px; }
label { font-weight: bold; display: block; }
input[type=text], input[type=password] { border: 1px solid black; padding: .2em; width: 465px; }
.button { padding: .2em .5em; float: right; }
fieldset { border: none; width: 465px; }
a { text-decoration: none; color: royalblue; display: block; padding: .2em; }
ul { list-style: none; margin: 0; padding: 0; }
li { display: block; float: left; margin: 5px 20px 5px 0; }
.createAccount { background-color: royalblue; color: white; padding: .2em .5em; }
</style>
On line 33 I added a class:
<a class="createAccount" href="/users-component/registration-form">Create an account</a>
You can change input[type=] adding a second class to username and password fields:
<input id="modlgn_username" type="text" name="username" class="inputbox text" size="18" /> I attached a screenshot result. Bye and good work.