diff --git a/booking.stripe.js b/booking.stripe.js
index b3b1a44..2c00488 100644
--- a/booking.stripe.js
+++ b/booking.stripe.js
@@ -23,6 +23,11 @@ jQuery(document).ready(function($) {
         }
     });
 
+    //attempt to update amount for amex cards
+    $('#card_number').blur(function() {
+        console.log(['Card field lost focus', $(this).attr('class')]);
+    });    
+
     $('.form-submit').click(function (e) {
         //currentForm = $(this).closest('form');
         //if (currentForm === undefined)
@@ -37,8 +42,9 @@ jQuery(document).ready(function($) {
         //alert($(':input[name="description"]', $stripeForm));
 
         //set the amount dynamically based on the card brand from the token
+        //this doesn't actually work since card_brand isn't set yet
         if ($(':input[name="card_brand"]', $stripeForm).val() == 'American Express') {
-            var $amount = $(':input[name="foreign_gross_amount"]', $stripeForm).val() * 100; 
+            var $amount = $(':input[name="foreign_gross_amount"]', $stripeForm).val() * 100;
         }
         else {
             var $amount = $(':input[name="gross_amount"]', $stripeForm).val() * 100; 
@@ -58,7 +64,7 @@ jQuery(document).ready(function($) {
         e.preventDefault();
     });
     // Close Checkout on page navigation
-    //$(window).on('popstate', function() {
-    //    handler.close();
-    //});
+    $(window).on('popstate', function() {
+        handler.close();
+    });
 });
\ No newline at end of file