diff --git a/src/ClaudeDo.Ui/Views/Planning/PlanningDiffView.axaml b/src/ClaudeDo.Ui/Views/Planning/PlanningDiffView.axaml
index 69b9c55..d0b3682 100644
--- a/src/ClaudeDo.Ui/Views/Planning/PlanningDiffView.axaml
+++ b/src/ClaudeDo.Ui/Views/Planning/PlanningDiffView.axaml
@@ -58,9 +58,7 @@
 
         <!-- Subtask list (left pane) -->
         <Border Grid.Column="0"
-                BorderBrush="{DynamicResource LineBrush}"
-                BorderThickness="0,0,1,0"
-                Background="{DynamicResource DeepBrush}">
+                Classes="sidebar-pane">
           <ListBox ItemsSource="{Binding Subtasks}"
                    SelectedItem="{Binding SelectedSubtask}"
                    IsEnabled="{Binding !IsCombinedMode}"