JSFiddle - React, Tailwind, and code Playground

HTML

<form name="no_account" action="http://www.pazzle.co.uk/index.php?main_page=no_account" method="post" onsubmit="return check_form(no_account);"><input type="hidden" name="securityToken" value="5a0a4b7acc7200adcdbd404d9081b420"><div><input type="hidden" name="action" value="process"><input type="hidden" name="email_pref_html" value="email_format">




  <fieldset id="billingField">
  <legend>Billing Address</legend>
  
    <br class="clearBoth">
  <br class="clearBoth">
    
  <label class="inputLabel" for="firstname">First Name:</label>
  <input type="text" name="firstname" size="33" maxlength="32" id="firstname"><span class="alert">*</span>  <br class="clearBoth">
  
  
  <label class="inputLabel" for="lastname">Last Name:</label>
  <input type="text" name="lastname" size="33" maxlength="32" id="lastname"><span class="alert">*</span>  <br class="clearBoth">
  
    
  <label class="inputLabel" for="street-address">Street Address:</label>
    <input type="text" name="street_address" size="41" maxlength="64" id="street-address"><span class="alert">*</span>  <br class="clearBoth">
  
    <label class="inputLabel" for="suburb">Address Line 2:</label>
  <input type="text" name="suburb" size="33" maxlength="32" id="suburb">  <br class="clearBoth">
    
  <label class="inputLabel" for="city">City:</label>
  <input type="text" name="city" size="33" maxlength="32" id="city"><span class="alert">*</span>  <br class="clearBoth">

    <div class="">  
    <label class="inputLabel" for="country">Country:</label>
    <select name="zone_country_id" id="country">
  <option value="">Please Choose Your Country</option>
  <option value="222" selected="selected">United Kingdom</option>
  <option value="240">Aaland Islands</option>
  <option value="1">Afghanistan</option>
  <option value="2">Albania</option>
  <option value="3">Algeria</option>
  <option value="4">American Samoa</option>
  <option value="5">Andorra</option>
  <option value="6">Angola</option>
  <option...

JavaScript

if($("#shippingAddress-checkbox").attr("checked") == "checked")
{
    $("#shippingField input:not(#shippingAddress-checkbox), #shippingField select:not(#shippingAddress-checkbox)").attr("disabled", "disabled");
}
else
{
    $("#shippingField input:not(#shippingAddress-checkbox), #shippingField select:not(#shippingAddress-checkbox)").removeAttr("disabled");               
}

$("#shippingAddress-checkbox").click(function(){
   if($(this).attr("checked") == "checked")
   {
       $("#shippingField input:not(#shippingAddress-checkbox), #shippingField select:not(#shippingAddress-checkbox)").attr("disabled", "disabled");
   }
   else
   {
       $("#shippingField input:not(#shippingAddress-checkbox), #shippingField select:not(#shippingAddress-checkbox)").removeAttr("disabled");               
   }
});