diff --git a/adventskalender/shared/style.css b/adventskalender/shared/style.css
index 6bb8a54..f104d37 100644
--- a/adventskalender/shared/style.css
+++ b/adventskalender/shared/style.css
@@ -48,7 +48,7 @@ main > h1 {
 
 /* === Bildcontainer === */
 .kalenderbild {
-  flex: 1 1 auto;
+  position: relative; /* Bezugsrahmen für Overlay */
   display: flex;
   align-items: center;
   justify-content: center;