add: redesign addUsers.html (#1407)

Co-authored-by: Anthony Stirling <77850077+Frooodle@users.noreply.github.com>

src/main/resources/templates/account.html

@@ -12,7 +12,7 @@
         <br><br>
         <div class="container">
           <div class="row justify-content-center">
-            <div class="col-md-9">
+            <div class="col-md-9 bg-card">
 
               <!-- User Settings Title -->
               <h2 class="text-center" th:text="#{account.accountSettings}">User Settings</h2>