diff --git a/web/html/xui/component/themeSwitch.html b/web/html/xui/component/themeSwitch.html
index f09b9be2..a94e8e6c 100644
--- a/web/html/xui/component/themeSwitch.html
+++ b/web/html/xui/component/themeSwitch.html
@@ -42,19 +42,29 @@
 
 {{define "component/ultraDarkTheme"}}
 <script>
-  const uthemeToggle = document.getElementById('ultra-dark-theme');
   const isUltraDarkThemeEnabled = localStorage.getItem('isUltraDarkThemeEnabled') === 'true';
-  uthemeToggle.checked = isUltraDarkThemeEnabled;
-  function ultraToggleTheme() {
-      if (uthemeToggle.checked) {
+
+  document.addEventListener('DOMContentLoaded', function () {
+    const uthemeToggle = document.getElementById('ultradarktheme');
+
+    if (uthemeToggle) {
+      uthemeToggle.checked = isUltraDarkThemeEnabled;
+
+      function ultraToggleTheme() {
+        if (uthemeToggle.checked) {
           document.documentElement.setAttribute('data-theme', 'ultra-dark');
           localStorage.setItem('isUltraDarkThemeEnabled', 'true');
-      } else {
+        } else {
           document.documentElement.removeAttribute('data-theme');
           localStorage.setItem('isUltraDarkThemeEnabled', 'false');
+        }
       }
-  }
-  uthemeToggle.addEventListener('change', ultraToggleTheme);
-  ultraToggleTheme();
-  </script>
+
+      uthemeToggle.addEventListener('change', ultraToggleTheme);
+      ultraToggleTheme();
+    } else {
+      console.error("Element with ID 'ultradarktheme' not found.");
+    }
+  });
+</script>
 {{end}}