diff --git a/app/web/static/compare.js b/app/web/static/compare.js
index 6b808bd..33d8a44 100644
--- a/app/web/static/compare.js
+++ b/app/web/static/compare.js
@@ -1,7 +1,7 @@
 // compare.js — thin shim that parses ?stem=…&stem=… (legacy ?a=&b=) and
 // hands off to panel-grid.js.
 
-import { mountPanels } from './panel-grid.js?v=5';
+import { mountPanels } from './panel-grid.js?v=6';
 
 const params = new URLSearchParams(window.location.search);
 let stems = params.getAll('stem').filter(Boolean);
diff --git a/app/web/static/panel-grid.js b/app/web/static/panel-grid.js
index ee67a19..7b60e80 100644
--- a/app/web/static/panel-grid.js
+++ b/app/web/static/panel-grid.js
@@ -567,6 +567,9 @@ export function mountPanels({ host, controls, stems }) {
   // Reset controls to a clean state (they may be reused across opens).
   if (scrub)   scrub.value = '0';
   if (playBtn) { playBtn.textContent = '▶'; playBtn.setAttribute('aria-label', 'play'); }
+  // Axes dropdown is meaningless for a single-panel view (nothing to lock
+  // against; aspect is fixed by the modal dialog's own sizing).
+  if (syncSel) syncSel.disabled = total < 2;
 
   // Parallel fetch; each panel's error is independent.
   const ready = Promise.allSettled(stems.map(fetchFrames)).then((results) => {
diff --git a/app/web/static/run-modal.js b/app/web/static/run-modal.js
index 29b0b39..6d48620 100644
--- a/app/web/static/run-modal.js
+++ b/app/web/static/run-modal.js
@@ -1,7 +1,7 @@
 // run-modal.js — homepage click-hijack for embedding links. Opens a
 // <dialog id="run-modal"> that renders the run's embedding via panel-grid.js.
 
-import { mountPanels } from './panel-grid.js?v=5';
+import { mountPanels } from './panel-grid.js?v=6';
 
 const dialog = document.getElementById('run-modal');
 const host = document.getElementById('modal-panel-host');
diff --git a/app/web/static/style.css b/app/web/static/style.css
index abae981..eb9ce39 100644
--- a/app/web/static/style.css
+++ b/app/web/static/style.css
@@ -1695,6 +1695,9 @@ button.submit:disabled { background: var(--faint); border-color: var(--faint); c
   align-items: center;
   gap: 0.35rem;
 }
+/* Hide a wrap entirely when its select is disabled (e.g., axes on a
+   single-panel modal view). */
+.compare-controls label:has(select:disabled) { display: none; }
 .compare-controls .cc-lbl {
   color: var(--faint);
   text-transform: lowercase;
diff --git a/app/web/templates/compare.html b/app/web/templates/compare.html
index e200d3f..073118c 100644
--- a/app/web/templates/compare.html
+++ b/app/web/templates/compare.html
@@ -102,7 +102,7 @@
 </template>
 
 <script src="/static/theme.js?v=11"></script>
-<script type="module" src="/static/compare.js?v=17"></script>
+<script type="module" src="/static/compare.js?v=18"></script>
 <!-- panel-grid.js is imported by compare.js (module); versioned via compare.js cache-bust -->
 
 </body>
diff --git a/app/web/templates/index.html b/app/web/templates/index.html
index 011c8a2..1e2d32f 100644
--- a/app/web/templates/index.html
+++ b/app/web/templates/index.html
@@ -4,7 +4,7 @@
   <meta charset="utf-8" />
   <meta name="viewport" content="width=device-width,initial-scale=1" />
   <title>embedding notebook</title>
-  <link rel="stylesheet" href="/static/style.css?v=36" />
+  <link rel="stylesheet" href="/static/style.css?v=37" />
   <script src="https://unpkg.com/htmx.org@2.0.4"></script>
   <script type="importmap">
   {
@@ -498,7 +498,7 @@
 <script type="module" src="/static/metrics.js?v=11"></script>
 <script src="/static/compare-select.js?v=2"></script>
 <script src="/static/runs-filter.js?v=3"></script>
-<script type="module" src="/static/run-modal.js?v=2"></script>
+<script type="module" src="/static/run-modal.js?v=3"></script>
 <script>
   // Anchor-links alone don't expand <details>; force it.
   document.querySelector('a[href="#metrics"]')?.addEventListener('click', () => {