diff --git a/html/assets/css/custom.scss b/html/assets/css/custom.scss
index 800fda8013f1e5b14813d8963ef912be279a1fd6..cd5000cf4000ffc251ac677f2de4496e2fe4b651 100644
--- a/html/assets/css/custom.scss
+++ b/html/assets/css/custom.scss
@@ -139,4 +139,5 @@ tr.begegnungen {
 
 img.flags {
   width: 20px;
+  border: 1px solid darkgrey;
 }