diff --git a/ZB.MOM.WW.Theme/src/ZB.MOM.WW.Theme/wwwroot/js/nav-state.js b/ZB.MOM.WW.Theme/src/ZB.MOM.WW.Theme/wwwroot/js/nav-state.js
index 4715c17..92c054a 100644
--- a/ZB.MOM.WW.Theme/src/ZB.MOM.WW.Theme/wwwroot/js/nav-state.js
+++ b/ZB.MOM.WW.Theme/src/ZB.MOM.WW.Theme/wwwroot/js/nav-state.js
@@ -1,10 +1,14 @@
 // ZB.MOM.WW.Theme nav-state.js — persists <details data-nav-key> open/closed
 // state in localStorage so NavRailSection expand state survives navigation and
 // reloads. Pure client-side; works with static Blazor SSR. Keyed per section.
+// localStorage keys are prefixed with "zbnav:" to avoid collisions.
 (function () {
     var PREFIX = "zbnav:";
+    var INIT_ATTR = "data-zbnav-initialized";
     function apply() {
         document.querySelectorAll("details.rail-section[data-nav-key]").forEach(function (el) {
+            if (el.hasAttribute(INIT_ATTR)) return; // already wired — avoid duplicate listeners
+            el.setAttribute(INIT_ATTR, "");
             var key = PREFIX + el.getAttribute("data-nav-key");
             var saved = null;
             try { saved = window.localStorage.getItem(key); } catch (e) { return; }