diff --git a/index.html b/index.html
index 45b3c79..9a23f01 100644
--- a/index.html
+++ b/index.html
@@ -13,9 +13,9 @@
   </header>
 
   <nav class="tabs">
-    <button class="tab-btn active" data-tab="employees">Mitarbeiter</button>
-    <button class="tab-btn" data-tab="planning">Monatsplanung</button>
-    <button class="tab-btn" data-tab="data">Daten</button>
+    <button type="button" class="tab-btn active" data-tab="employees">Mitarbeiter</button>
+    <button type="button" class="tab-btn" data-tab="planning">Monatsplanung</button>
+    <button type="button" class="tab-btn" data-tab="data">Daten</button>
   </nav>
 
   <main>