diff --git a/k8s/apps/syncthing/nginx-router.yaml b/k8s/apps/syncthing/nginx-router.yaml
index ad6a3dd..7e78890 100644
--- a/k8s/apps/syncthing/nginx-router.yaml
+++ b/k8s/apps/syncthing/nginx-router.yaml
@@ -49,9 +49,8 @@ data:
             sub_filter '"/vendor' '"/nas/vendor';
             sub_filter '"/theme-assets' '"/nas/theme-assets';
             sub_filter '"/syncthing' '"/nas/syncthing';
-            # Add floating back button
-            sub_filter '</head>' '</head><style>.syncthing-back-btn { position: fixed !important; top: 60px !important; left: 10px !important; z-index: 10000 !important; background: #0078e7 !important; color: white !important; padding: 8px 16px !important; border-radius: 4px !important; text-decoration: none !important; display: inline-block !important; box-shadow: 0 2px 4px rgba(0,0,0,0.2) !important; }</style>';
-            sub_filter '<div class="container">' '<a href="/" class="syncthing-back-btn">← Back to Instances</a><div class="container">';
+            # Add floating back button via JavaScript
+            sub_filter '</body>' '<script>document.addEventListener("DOMContentLoaded", function() { var btn = document.createElement("a"); btn.href = "/"; btn.innerHTML = "← Back to Instances"; btn.style.cssText = "position: fixed; top: 70px; left: 10px; z-index: 10000; background: #0078e7; color: white; padding: 8px 16px; border-radius: 4px; text-decoration: none; display: block; box-shadow: 0 2px 4px rgba(0,0,0,0.2);"; document.body.appendChild(btn); });</script></body>';
             sub_filter_once off;
             sub_filter_types text/html text/css application/javascript;
         }
@@ -94,9 +93,8 @@ data:
             sub_filter '"/vendor' '"/master/vendor';
             sub_filter '"/theme-assets' '"/master/theme-assets';
             sub_filter '"/syncthing' '"/master/syncthing';
-            # Add floating back button
-            sub_filter '</head>' '</head><style>.syncthing-back-btn { position: fixed !important; top: 60px !important; left: 10px !important; z-index: 10000 !important; background: #0078e7 !important; color: white !important; padding: 8px 16px !important; border-radius: 4px !important; text-decoration: none !important; display: inline-block !important; box-shadow: 0 2px 4px rgba(0,0,0,0.2) !important; }</style>';
-            sub_filter '<div class="container">' '<a href="/" class="syncthing-back-btn">← Back to Instances</a><div class="container">';
+            # Add floating back button via JavaScript
+            sub_filter '</body>' '<script>document.addEventListener("DOMContentLoaded", function() { var btn = document.createElement("a"); btn.href = "/"; btn.innerHTML = "← Back to Instances"; btn.style.cssText = "position: fixed; top: 70px; left: 10px; z-index: 10000; background: #0078e7; color: white; padding: 8px 16px; border-radius: 4px; text-decoration: none; display: block; box-shadow: 0 2px 4px rgba(0,0,0,0.2);"; document.body.appendChild(btn); });</script></body>';
             sub_filter_once off;
             sub_filter_types text/html text/css application/javascript;
         }
@@ -139,9 +137,8 @@ data:
             sub_filter '"/vendor' '"/iris/vendor';
             sub_filter '"/theme-assets' '"/iris/theme-assets';
             sub_filter '"/syncthing' '"/iris/syncthing';
-            # Add floating back button
-            sub_filter '</head>' '</head><style>.syncthing-back-btn { position: fixed !important; top: 60px !important; left: 10px !important; z-index: 10000 !important; background: #0078e7 !important; color: white !important; padding: 8px 16px !important; border-radius: 4px !important; text-decoration: none !important; display: inline-block !important; box-shadow: 0 2px 4px rgba(0,0,0,0.2) !important; }</style>';
-            sub_filter '<div class="container">' '<a href="/" class="syncthing-back-btn">← Back to Instances</a><div class="container">';
+            # Add floating back button via JavaScript
+            sub_filter '</body>' '<script>document.addEventListener("DOMContentLoaded", function() { var btn = document.createElement("a"); btn.href = "/"; btn.innerHTML = "← Back to Instances"; btn.style.cssText = "position: fixed; top: 70px; left: 10px; z-index: 10000; background: #0078e7; color: white; padding: 8px 16px; border-radius: 4px; text-decoration: none; display: block; box-shadow: 0 2px 4px rgba(0,0,0,0.2);"; document.body.appendChild(btn); });</script></body>';
             sub_filter_once off;
             sub_filter_types text/html text/css application/javascript;
         }