Add ghost sign-up form

index.html

@@ -10,6 +10,9 @@ <h1 class="tc mb3">Heart of Clojure</h1>
   </div>
   <p class="f3 tc">We're back, baby! Five years after the legendary first edition, Heart of Clojure returns.</p>
   <p class="f3 tc">Coming to Leuven, Belgium. Fall 2024.</p>
+  <div style="min-height: 58px; max-width: 440px;width: 100%;position: absolute; left: 50%; top:50%; transform: translate(-50%, -50%);">
+    <script src="https://cdn.jsdelivr.net/ghost/signup-form@~0.1/umd/signup-form.min.js" data-button-color="#197eff" data-button-text-color="#FFFFFF" data-site="https://gaiwan.co/" async> </script>
+  </div>
 </div>
 
 <!-- <div class="mw7 pa3 center lh-copy f4"> -->