improve babillard page

src/babillard_page.eml.html

@@ -1,16 +1,15 @@
 let f request =
   <script type="text/javascript" src="/assets/js/js_babillard.js" defer="defer"></script>
-<%s  Format.sprintf "Babillard is love" %>
+  <h1>Babillard is love ❤️</h1>
+  <br />
   <div class="row mb-3">
     <div class="col-md-6">
-% begin match Dream.session "nick" request with
-% | None ->
-
-% | Some _nick ->
+% if Option.is_some @@ Dream.session "nick" request then begin
       <a href="/babillard/new_thread" >[New Thread]</a>
 % end;
       <div id="map"></div>
-<button onclick="geolocalize()">Geolocalize me</button>
+      <br />
+      <button class="btn btn-primary" onclick="geolocalize()">Geolocalize me</button>
     </div>
     <div class="col-md-6">
       <div id="thread_preview_div"></div>