diff --git a/web/static/map.js b/web/static/map.js
index 23a554f..82ac01b 100644
--- a/web/static/map.js
+++ b/web/static/map.js
@@ -37,10 +37,8 @@ function initMap() {
     map.createPane('diffPane');
     map.createPane('countyPane');
 
-    // Set initial z-indices for panes
-    map.getPane('osmPane').style.zIndex = 400;
-    map.getPane('diffPane').style.zIndex = 401;
-    map.getPane('countyPane').style.zIndex = 402;
+    // Set initial z-indices for panes based on layerOrder
+    updateLayerZIndex();
 
     // Setup drag selection
     setupDragSelection();
@@ -1100,14 +1098,30 @@ function updateLayerZIndex() {
         'county': 'countyPane'
     };
 
+    const layers = {
+        'osm': osmLayer,
+        'diff': diffLayer,
+        'county': countyLayer
+    };
+
     // Reverse index so first item in list is on top
+    // Use higher base z-index (650) to ensure we're above overlay pane
     layerOrder.forEach((layerName, index) => {
         const paneName = panes[layerName];
         const pane = map.getPane(paneName);
         if (pane) {
-            pane.style.zIndex = 400 + (layerOrder.length - 1 - index);
+            const zIndex = 650 + (layerOrder.length - 1 - index);
+            pane.style.zIndex = zIndex;
         }
     });
+
+    // Also bring layers to front in reverse order (last first, so first ends up on top)
+    for (let i = layerOrder.length - 1; i >= 0; i--) {
+        const layer = layers[layerOrder[i]];
+        if (layer && map.hasLayer(layer)) {
+            layer.bringToFront();
+        }
+    }
 }
 
 // Toggle layer visibility
@@ -1117,13 +1131,15 @@ function toggleLayer(layerId, layer) {
     if (checkbox.checked && layer) {
         if (!map.hasLayer(layer)) {
             map.addLayer(layer);
-            updateLayerZIndex();
         }
     } else if (layer) {
         if (map.hasLayer(layer)) {
             map.removeLayer(layer);
         }
     }
+
+    // Always update z-index after toggling any layer
+    updateLayerZIndex();
 }
 
 // Event listeners