diff --git a/app/gui/theme.py b/app/gui/theme.py
index 785bd38..82e4edf 100644
--- a/app/gui/theme.py
+++ b/app/gui/theme.py
@@ -31,12 +31,16 @@ class ThemeMixin:
         """Initialise ttk style handling and apply the detected theme."""
         if HAS_TTKBOOTSTRAP:
             try:
-                # Ensure msgcat package is available before ttkbootstrap initialises translations
-                self.root.tk.call("package", "require", "msgcat")  # type: ignore[attr-defined]
+                try:
+                    self.root.tk.call("package", "require", "msgcat")  # type: ignore[attr-defined]
+                except Exception:
+                    pass
+                self.style = tb.Style()
+                self.using_tb = True
             except Exception:
-                pass
-            self.style = tb.Style()
-            self.using_tb = True
+                self.style = ttk.Style()
+                self.style.theme_use("clam")
+                self.using_tb = False
         else:
             self.style = ttk.Style()
             self.style.theme_use("clam")