diff --git a/MyTimeline.py b/MyTimeline.py
index cfa2033..cc67abe 100644
--- a/MyTimeline.py
+++ b/MyTimeline.py
@@ -89,6 +89,15 @@ CLICKABLE_AREA_HEIGHT = 30
 YEAR_LABEL_WIDTH = 100
 YEAR_MARKER_STEP_DIVISOR = 10  # Divisor for calculating year marker step (every Nth year)
 TOOLTIP_DELAY = 500  # milliseconds
+
+# Drawing Area Event Masks
+DRAWING_AREA_EVENT_MASKS = (
+    Gdk.EventMask.BUTTON_PRESS_MASK 
+    | Gdk.EventMask.BUTTON_RELEASE_MASK
+    | Gdk.EventMask.POINTER_MOTION_MASK
+    | Gdk.EventMask.LEAVE_NOTIFY_MASK
+    | Gdk.EventMask.SCROLL_MASK
+)
 TOOLTIP_MAX_WIDTH = 500
 LABEL_BACKGROUND_PADDING = 8
 LABEL_BACKGROUND_RADIUS = 5
@@ -644,13 +653,7 @@ class MyTimelineView(NavigationView):
         self.drawing_area = Gtk.DrawingArea()
         self.drawing_area.set_size_request(800, 600)
         self.drawing_area.connect("draw", self.on_draw)
-        self.drawing_area.add_events(
-            Gdk.EventMask.BUTTON_PRESS_MASK 
-            | Gdk.EventMask.BUTTON_RELEASE_MASK
-            | Gdk.EventMask.POINTER_MOTION_MASK
-            | Gdk.EventMask.LEAVE_NOTIFY_MASK
-            | Gdk.EventMask.SCROLL_MASK
-        )
+        self.drawing_area.add_events(DRAWING_AREA_EVENT_MASKS)
         
         # Connect mouse events
         self.drawing_area.connect("button-press-event", self.on_button_press)