diff --git a/src/components/MainContent.vue b/src/components/MainContent.vue
index 4453ae9..87994dc 100644
--- a/src/components/MainContent.vue
+++ b/src/components/MainContent.vue
@@ -37,7 +37,6 @@
   // Panning state
   const isPanning = ref(false);
   const isAltPressed = ref(false);
-  const isMiddleMouseDown = ref(false);
   const lastPosition = ref({ x: 0, y: 0 });
 
   // Tooltip state