diff --git a/plugin-designs/plugin-studio/plugin-studio.vue b/plugin-designs/plugin-studio/plugin-studio.vue
index 84961b822..49bc0ab38 100644
--- a/plugin-designs/plugin-studio/plugin-studio.vue
+++ b/plugin-designs/plugin-studio/plugin-studio.vue
@@ -223,6 +223,13 @@ const PS_SHADOW_CSS = `
 .ps-logo { display:inline-flex; align-items:center; }
 .ps-logo svg { display:block; }
 .ps-count { color:#6d766e; }
+/* THE HEADER'S MENUS SIT ABOVE EVERY PLUGIN (Driver, 2026-09-25: "the Mapbox token menu is not on top …
+   it is underlapping the plugins"). The header row and the pane area are siblings with no stacking context
+   of their own, so a menu at z-index 30 competed with each plugin's own chrome (a filter bar at 55, a drawer
+   at 1000) and lost. The header now stacks above the content, and the pane area is ISOLATED: whatever
+   z-index a plugin uses stays inside its pane. */
+.vtl-top { position:relative; z-index:3; }
+.vtl-body { isolation:isolate; }
 .ps-token { position:relative; display:inline-flex; }
 .ps-token-dot { width:8px; height:8px; border-radius:50%; background:#b8bdb4; }
 .ps-token-dot.is-yours, .ps-token-dot.is-url { background:#92b195; }
@@ -1058,6 +1065,13 @@ export default defineComponent({
 .ps-logo { display: inline-flex; align-items: center; }
 .ps-logo svg { display: block; }
 .ps-count { color: #6d766e; }
+/* THE HEADER'S MENUS SIT ABOVE EVERY PLUGIN (Driver, 2026-09-25: "the Mapbox token menu is not on top …
+   it is underlapping the plugins"). The header row and the pane area are siblings with no stacking context
+   of their own, so a menu at z-index 30 competed with each plugin's own chrome (a filter bar at 55, a drawer
+   at 1000) and lost. The header now stacks above the content, and the pane area is ISOLATED: whatever
+   z-index a plugin uses stays inside its pane. */
+.vtl-top { position:relative; z-index:3; }
+.vtl-body { isolation:isolate; }
 .ps-token { position:relative; display:inline-flex; }
 .ps-token-dot { width:8px; height:8px; border-radius:50%; background:#b8bdb4; }
 .ps-token-dot.is-yours, .ps-token-dot.is-url { background:#92b195; }