diff --git a/www/src/index.md b/www/src/index.md
index 29cac79..e0ab5eb 100644
--- a/www/src/index.md
+++ b/www/src/index.md
@@ -14,6 +14,7 @@ Welcome to instant, interoperable and [privacy-preserving](privacy.html) messagi
 
 💬 **Start** chatting with any Delta Chat contacts using [QR invite codes](https://delta.chat/en/help#howtoe2ee)
 
+<div class="experimental">Note: this is an experimental service</div>
+
 
-## ⚡ Note: this is an experimental service ⚡
 
diff --git a/www/src/main.css b/www/src/main.css
index 2f7e5a2..cf7fabf 100644
--- a/www/src/main.css
+++ b/www/src/main.css
@@ -21,3 +21,11 @@
 .banner {
   width: 100%;
 }
+
+.experimental {
+  margin: 3em 0;
+  padding: 1em;
+  border: 4px dashed red;
+  color: red;
+  font-weight: bold;
+}