diff --git a/frontend/assets/js/app.js b/frontend/assets/js/app.js
index 4c4aa17..b3279e1 100644
--- a/frontend/assets/js/app.js
+++ b/frontend/assets/js/app.js
@@ -32,6 +32,22 @@ let copyBuffer = null;
 let editingNodeId = null;
 let editingShapeId = null;
 
+const DOC_TYPE_ICONS = {
+    deployment: { icon: 'fa-server', color: '#06b6d4' },
+    attack: { icon: 'fa-bolt', color: '#ef4444' },
+    'incident-report': { icon: 'fa-exclamation-triangle', color: '#f59e0b' },
+    remediation: { icon: 'fa-wrench', color: '#22c55e' },
+    exercise: { icon: 'fa-dumbbell', color: '#3b82f6' }
+};
+
+const DOC_TYPE_LABELS = {
+    deployment: 'Deployment',
+    attack: 'Attack',
+    'incident-report': 'Incident Report',
+    remediation: 'Remediation',
+    exercise: 'Exercise'
+};
+
 // ==================== AUTH / SESSION ====================
 let currentUser = null;
 let currentRole = null;
@@ -1036,10 +1052,25 @@ function esc(s) {
 async function loadRegistrationSetting() {
     try {
         const res = await apiFetch('registration');
-        document.getElementById('registrationToggle').checked = res.registration_enabled === true;
+        const toggle = document.getElementById('registrationToggle');
+        if (toggle) toggle.checked = res.registration_enabled === true;
     } catch (e) {}
 }
 
+async function saveRegistrationSetting() {
+    const toggle = document.getElementById('registrationToggle');
+    if (!toggle) return;
+    const enabled = toggle.checked;
+    try {
+        await apiFetch('registration', {
+            method: 'POST',
+            body: JSON.stringify({ registration_enabled: enabled })
+        });
+    } catch (e) {
+        alert('Failed to update registration setting');
+    }
+}
+
 async function loadUsers() {
     const list = document.getElementById('userList');
     try {
@@ -1090,21 +1121,6 @@ document.getElementById('settingsModal').addEventListener('show.bs.modal', () =>
 document.getElementById('registrationToggle').addEventListener('change', saveRegistrationSetting);
 
 // ==================== DOCUMENTS ====================
-const DOC_TYPE_ICONS = {
-    deployment: { icon: 'fa-server', color: '#06b6d4' },
-    attack: { icon: 'fa-bolt', color: '#ef4444' },
-    'incident-report': { icon: 'fa-exclamation-triangle', color: '#f59e0b' },
-    remediation: { icon: 'fa-wrench', color: '#22c55e' },
-    exercise: { icon: 'fa-dumbbell', color: '#3b82f6' }
-};
-
-const DOC_TYPE_LABELS = {
-    deployment: 'Deployment',
-    attack: 'Attack',
-    'incident-report': 'Incident Report',
-    remediation: 'Remediation',
-    exercise: 'Exercise'
-};
 
 async function loadDocuments() {
     try {