diff --git a/packages/frontend/src/shell/DashboardCalendarTab.tsx b/packages/frontend/src/shell/DashboardCalendarTab.tsx
index 3cffe09..5f01fd0 100644
--- a/packages/frontend/src/shell/DashboardCalendarTab.tsx
+++ b/packages/frontend/src/shell/DashboardCalendarTab.tsx
@@ -74,13 +74,8 @@ function getEventsForDay(events: M365CalendarEvent[], day: Date): M365CalendarEv
     );
 }
 
-// Deterministische Farbe anhand Event-ID
-const EVENT_COLORS = ['#3b82f6', '#8b5cf6', '#ec4899', '#f59e0b', '#10b981', '#ef4444'];
-function eventColor(id: string): string {
-  let h = 0;
-  for (const ch of id) h = (h * 31 + ch.charCodeAt(0)) % EVENT_COLORS.length;
-  return EVENT_COLORS[h];
-}
+// Einheitliche Farbe für alle Kalendereinträge (Primary-Blau)
+const EVENT_COLOR = 'var(--color-primary)';
 
 // ── Calendar Event Detail Modal ────────────────────────────────────────────────
 
@@ -351,7 +346,7 @@ export function DayAgenda({
             <div
               key={event.id}
               className={styles.agendaItem}
-              style={{ borderLeftColor: eventColor(event.id), cursor: 'pointer' }}
+              style={{ borderLeftColor: EVENT_COLOR, cursor: 'pointer' }}
               role="button"
               tabIndex={0}
               onClick={() => onEventClick?.(event)}
@@ -441,7 +436,7 @@ function AgendaView({
                   <div
                     key={e.id}
                     className={styles.agendaFullEvent}
-                    style={{ borderLeftColor: eventColor(e.id), cursor: 'pointer' }}
+                    style={{ borderLeftColor: EVENT_COLOR, cursor: 'pointer' }}
                     role="button"
                     tabIndex={0}
                     onClick={(ev) => {
@@ -528,7 +523,7 @@ function MonthView({
                 <div
                   key={e.id}
                   className={styles.eventChip}
-                  style={{ background: eventColor(e.id) }}
+                  style={{ background: EVENT_COLOR }}
                   title={`${formatTime(e.start.dateTime, e.start.timeZone)} ${e.subject}`}
                 >
                   {formatTime(e.start.dateTime, e.start.timeZone)} {e.subject}
@@ -593,7 +588,7 @@ function WeekView({
                 <div
                   key={e.id}
                   className={styles.weekEvent}
-                  style={{ borderLeftColor: eventColor(e.id) }}
+                  style={{ borderLeftColor: EVENT_COLOR }}
                   title={e.subject}
                   onClick={(ev) => {
                     ev.stopPropagation();