start buy button

not working fully, not counting clicks

buy.php

@@ -0,0 +1,11 @@
+<?php
+
+    $to = "mail@jan-patrick.de";
+    $from = $_POST['email'];
+    $name = $_POST['name'];
+    $header = "Neue Nachricht von $from";
+    $subject = $_POST['subject'];
+
+    $send = mail($to, $subject, $body, $header);
+
+?>

index.html

@@ -64,7 +64,10 @@
     <header class="masthead">
       <div class="container d-flex h-100 align-items-center">
         <div class="mx-auto text-center">
-          <br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br> <a href="#about" class="btn btn-primary js-scroll-trigger">start</a>
+          <br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br><br>
+          <button type="button" class="btn btn-primary" data-toggle="modal" data-target="#buyModalCenter">
+              jetzt kaufen
+          </button>
         </div>
       </div>
     </header>
@@ -222,8 +225,11 @@ <h4 class="text-white">Datenverarbeitung</h4>
         <div class="row">
           <div class="col-md-10 col-lg-8 mx-auto text-center">
 
-            <a href="mailto:hi@sense-chess.de"><i class="far fa-paper-plane fa-2x mb-2 text-white"></i>
-            <h2 class="text-white mb-5">mehr Information</h2></a>
+            <button type="button" class="btn btn-primary" data-toggle="modal" data-target="#buyModalCenter">
+              jetzt kaufen
+            </button>
+            <div class="mx-auto text-center">
+              </div>
           </div>
         </div>
       </div>
@@ -293,6 +299,46 @@ <h4 class="text-uppercase m-0">Prototyp</h4>
       </div>
     </footer>
 
+    <!-- Modal -->
+    <div class="modal fade" id="buyModalCenter" tabindex="-1" role="dialog" aria-labelledby="buyModalCenterTitle" aria-hidden="true">
+      <div class="modal-dialog modal-dialog-centered" role="document">
+        <div class="modal-content">
+          <div class="modal-header">
+            <h5 class="modal-title" id="buyModalLongTitle">Interesse an sense-chess?</h5>
+            <button type="button" class="close" data-dismiss="modal" aria-label="Close">
+              <span aria-hidden="true">&times;</span>
+            </button>
+          </div>
+          <div class="modal-body">
+              <form class="form-signin" id="mail_subscribe" method="post" action="buy.php" role="form" target="">
+                  <div class="text-left mb-4">
+                    <p>Leider ist sense-chess bisher nicht käuflich erhältlich. <br>Sie dürfen uns bei Interesse aber gerne kontaktieren:</p>
+                  </div>
+
+                  <div class="form-label-group">
+                    <label for="inputName">Name</label>
+                    <input type="name" id="inputEmail" class="form-control" placeholder="Ihr Name" name="name" required>
+                  </div>
+                  <br>
+                  <div class="form-label-group">
+                    <label for="inputEmail">E-Mail</label>
+                    <input type="email" id="inputEmail" class="form-control" placeholder="Ihre Mailadresse" name="email" required>
+                  </div>
+                  <br>
+                  <div class="form-label-group">
+                      <label for="inputEmail">Nachricht</label>
+                      <input type="text" id="inputMessage" class="form-control" placeholder="Ihre Nachricht" name="subject" required>
+                    </div>
+                    <br><br>
+                    <input type="submit" class="btn btn-success btn-send" value="Senden" target="">
+                    <button type="button" class="btn btn-primary" data-dismiss="modal">Schliessen</button>
+                  <br>  
+                </form>
+          </div>
+        </div>
+      </div>
+    </div>
+
     <!-- Bootstrap core JavaScript -->
     <script src="vendor/jquery/jquery.min.js"></script>
     <script src="vendor/bootstrap/js/bootstrap.bundle.min.js"></script>
@@ -320,6 +366,15 @@ <h4 class="text-uppercase m-0">Prototyp</h4>
       }
     </script>
 
+    <script>
+      $('#mail_subscribe').submit(function() {
+        var post_data = $('#mail_subscribe').serialize();
+        $.post('buy.php', post_data, function(data) {
+        });
+      });
+
+    </script>
+
   </body>
 
 </html>