diff --git a/src/ui/__pycache__/main_window.cpython-311.pyc b/src/ui/__pycache__/main_window.cpython-311.pyc
new file mode 100644
index 0000000..905a76a
Binary files /dev/null and b/src/ui/__pycache__/main_window.cpython-311.pyc differ
diff --git a/src/ui/main_window.py b/src/ui/main_window.py
index b58c73f..37f6232 100644
--- a/src/ui/main_window.py
+++ b/src/ui/main_window.py
@@ -8,7 +8,7 @@ from PySide6.QtWidgets import (
     QStackedWidget, QStatusBar, QMenuBar, QMenu,
     QLabel, QFrame, QSplitter, QSizePolicy
 )
-from PySide6.QtCore import Qt, QSize
+from PySide6.QtCore import Qt, QSize, Signal
 from PySide6.QtGui import QAction, QIcon
 
 from .theme import ThemeColors, ThemeQSS
@@ -70,7 +70,7 @@ class TitleBar(QWidget):
 class NavigationBar(QWidget):
     """Left side navigation bar."""
     
-    navigation_changed = QtSignal(str)
+    navigation_changed = Signal(str)
     
     def __init__(self, parent=None):
         super().__init__(parent)