Fishbowl Subscription Input Form adapting to WordPress Theme form style

Hello,
Fishbowl: https://www.fishbowl.com/

Is a popular restaurant email/newsletter subscription and analysis service for restaurants. They provide some HTML and javascript (not necessary just for email validation) code to use to subscribe to their service. So when a customer signs up on your website with an email, there address sis added to an email list on their website.

I want to use their code in the Milano contact form theme with the styling.

Here is the template of code they send you to use.
I noticed Milano email form code is using:

[th-contact-form subject=”Preferred Guest Registration” to=”[email protected]” button_text=”Submit”]

for the email code.

While they use:

<form action="https://yourhostname.fbmta.com/members/subscribe.aspx" method="post"
 onSubmit="return validateEmail(this.EmailAddress.value);">
<input name="Submit" type="submit" value="Submit">

Here is there template code to tweak, any advice on where next to proceed would be appreciated. I was in the middle of adding the “form action -contact form” commands to the “th-contact-form subject” code:

This is the whole HTML code template for subscribing Fishbowl sends to tweak:

<script language="Javascript" type="text/javascript">
   function validateEmail(emailAddress) {
      /* NOTE:  This regular expression is identical to the one used by Enterprise for e-mail address validation */
      var regExp =
/^\s*[a-zA-Z\d][a-zA-Z\d\.!#$%&'*+\-\/=?^_

{|}~]*@([a-zA-Z0-9]([a-zA-Z0-9\-]{0,61}[a-zA-Z0-9])?\.)+[a-zA-Z]{2,6}\s*$/;
      if (emailAddress.length <= 200 && regExp.test(emailAddress)) {
         return true;
      } else {
         alert("Invalid e-mail address");
         return false;
      }
   }
</script>

<form action="https://yourhostname.fbmta.com/members/subscribe.aspx" method="post"
 onSubmit="return validateEmail(this.EmailAddress.value);">
<input type="hidden" name="Action" id="Action" value="subscribe" size="30" maxlength="200">
<!-- EmailAddress must not be greater than 200 characters -->
<input type="text" name="EmailAddress" id="EmailAddress" value="Enter your e-mail address" size="30" maxlength="200">
<!-- ListID(s) can be found on the Manage Lists page in Enterprise -->
<input type="hidden" name="ListID" value="957293,950223">
<!-- SiteGUID will be supplied by Fishbowl Client Support -->
<input type="hidden" name="SiteGUID" value="12345678-90ab-cdef-1234-567890abcdef">
<!-- ReturnURL is the absolute URL of a Web page to which the user will be redirected after submitting the form -->
<input type="hidden" name="ReturnURL" value="https://yourdomainname/yourconfirmationpage">
<!--SuppressConfirmation should be set to "true" or "yes" if Enterprise should NOT send a confirmation e-mail to the subscriber notifying him or her of the subscription/profile update; omitting SuppressConfirmation has the same effect as explicitly setting a value of "false" or "no" -->
<input type="hidden" name="SuppressConfirmation" value="yes">
<input name="Submit" type="submit" value="Submit">
</form>