More issues with REST API integration

I'm now having issues changing the submit (check) button to reflect, well anything that would resemble a button. I've tried changing the code itself to reflect the css style of the theme's buttons but still nothing. Please reference and I'll copy the current code below. Mind you this is the code provided by my billing/invoicing company to be able to integrate with there REST API.


<form accept-charset="UTF-8" action="" method="post"><div style="margin:0;padding:10px;display:inline"></div>
<h6>Let's Check On Your Device</h6>
<div class="login-fields">
<h5>Sign in using ticket number and last name:</h5>
<div class="field">
<label for="username"><span style="font-family: 'Cronos Pro Display', 'Cronos Pro Light', 'Cronos Pro Caption', 'Cronos Pro'; font-style: normal; font-size: 18px;"><span style="color: #ffffff">Ticket Number:</span></span>:</label>
<input id="ticket_number" name="ticket_number" placeholder="Ticket #" type="text" />
<!-- /field -->
<div class="field">
<label for="password" style="font-size: 18px; font-family: 'Cronos Pro Display', 'Cronos Pro Light', 'Cronos Pro Caption', 'Cronos Pro';"><span style="color: #ffffff">Last Name</span></label>
<span style="color: #FFFFFF"></span>
<input name="last_name" type="text" class="login username-field" id="last_name" placeholder="Last Name" autocomplete="off" /></br>
</div> <!-- /password -->
</div> <!-- /login-fields -->

<div class="login-actions">
<input class="request-button" name="commit" type="submit" value="Check" />
</div> <!-- .actions --></br>