diff --git a/js/event-popup.js b/js/event-popup.js
index eb35e11..eb893a8 100644
--- a/js/event-popup.js
+++ b/js/event-popup.js
@@ -31,17 +31,13 @@
 
   function formatDate(isoStr) {
     if (!isoStr) return "";
-    var d = new Date(isoStr);
-    if (isNaN(d.getTime())) return isoStr;
-    return (
-      pad2(d.getDate()) + "." + pad2(d.getMonth() + 1) + "." + d.getFullYear()
-    );
+    var match = isoStr.match(/^(\d{4})-(\d{2})-(\d{2})/);
+    if (!match) return isoStr;
+    return match[3] + "." + match[2] + "." + match[1];
   }
 
   function formatDateTime(isoStr) {
     if (!isoStr) return "";
-    var d = new Date(isoStr);
-    if (isNaN(d.getTime())) return isoStr;
     return formatDate(isoStr) + " " + formatTimeOnly(isoStr);
   }
 
@@ -435,14 +431,12 @@
         var startTime = "";
         var endTime = "";
         if (!data.allDay && data.start) {
-          var sd = new Date(data.start);
-          if (!isNaN(sd.getTime()))
-            startTime = pad2(sd.getHours()) + ":" + pad2(sd.getMinutes());
+          startTime = formatTimeOnly(data.start);
+          if (startTime === data.start) startTime = "";
         }
         if (!data.allDay && data.end) {
-          var ed = new Date(data.end);
-          if (!isNaN(ed.getTime()))
-            endTime = pad2(ed.getHours()) + ":" + pad2(ed.getMinutes());
+          endTime = formatTimeOnly(data.end);
+          if (endTime === data.end) endTime = "";
         }
 
         renderForm(