diff --git a/src/app/exercise/[id]/ExercisePageClient.tsx b/src/app/exercise/[id]/ExercisePageClient.tsx
index d80c3bf..cbef560 100644
--- a/src/app/exercise/[id]/ExercisePageClient.tsx
+++ b/src/app/exercise/[id]/ExercisePageClient.tsx
@@ -150,10 +150,6 @@ export default function ExercisePageClient({ params }: { params: Promise<{ id: s
   const pathname = usePathname();
   const [isMobile, setIsMobile] = useState(false);
   const [activeMobileTab, setActiveMobileTab] = useState<'source' | 'viz' | 'log' | 'misc'>('source');
-  const mobileShellRef = useRef<HTMLDivElement | null>(null);
-  const mobileWorkspacePanelRef = useRef<HTMLDivElement | null>(null);
-  const mobileDirectionsRef = useRef<HTMLDivElement | null>(null);
-  const mobileBottomDockRef = useRef<HTMLDivElement | null>(null);
 
   useEffect(() => {
     if (typeof window === 'undefined') return;
@@ -209,67 +205,6 @@ export default function ExercisePageClient({ params }: { params: Promise<{ id: s
     setActiveMobileTab('source');
   }, [id]);
 
-  useEffect(() => {
-    if (!isMobile) {
-      mobileShellRef.current?.style.removeProperty('--mobile-workspace-panel-height');
-      return;
-    }
-
-    const shellElement = mobileShellRef.current;
-    const panelElement = mobileWorkspacePanelRef.current;
-    const directionsElement = mobileDirectionsRef.current;
-    const bottomDockElement = mobileBottomDockRef.current;
-
-    if (!shellElement || !panelElement || !directionsElement || !bottomDockElement) {
-      return;
-    }
-
-    let frameId = 0;
-
-    const syncPanelHeight = () => {
-      frameId = 0;
-      const shellRect = shellElement.getBoundingClientRect();
-      const panelRect = panelElement.getBoundingClientRect();
-      const bottomDockRect = bottomDockElement.getBoundingClientRect();
-      const shellStyles = window.getComputedStyle(shellElement);
-      const shellGap = parseFloat(shellStyles.rowGap || shellStyles.gap || '0') || 0;
-      const availableHeight = Math.floor(bottomDockRect.top - panelRect.top - shellGap);
-      const maxAvailableHeight = Math.floor(shellRect.bottom - panelRect.top);
-      const nextHeight = Math.max(0, Math.min(availableHeight, maxAvailableHeight));
-      shellElement.style.setProperty('--mobile-workspace-panel-height', `${nextHeight}px`);
-    };
-
-    const queueSyncPanelHeight = () => {
-      if (frameId !== 0) return;
-      frameId = window.requestAnimationFrame(syncPanelHeight);
-    };
-
-    queueSyncPanelHeight();
-
-    const observer = new ResizeObserver(() => {
-      queueSyncPanelHeight();
-    });
-
-    observer.observe(shellElement);
-    observer.observe(directionsElement);
-    observer.observe(bottomDockElement);
-
-    window.addEventListener('resize', queueSyncPanelHeight);
-    window.visualViewport?.addEventListener('resize', queueSyncPanelHeight);
-    window.visualViewport?.addEventListener('scroll', queueSyncPanelHeight);
-
-    return () => {
-      observer.disconnect();
-      window.removeEventListener('resize', queueSyncPanelHeight);
-      window.visualViewport?.removeEventListener('resize', queueSyncPanelHeight);
-      window.visualViewport?.removeEventListener('scroll', queueSyncPanelHeight);
-      if (frameId !== 0) {
-        window.cancelAnimationFrame(frameId);
-      }
-      shellElement.style.removeProperty('--mobile-workspace-panel-height');
-    };
-  }, [activeMobileTab, isMobile]);
-
   useEffect(() => {
     const mainElement = document.querySelector('#app-body > main');
     const appElement = document.getElementById('app');
@@ -512,8 +447,8 @@ export default function ExercisePageClient({ params }: { params: Promise<{ id: s
 
   if (isMobile) {
     return (
-      <div className="mobile-exercise-shell" ref={mobileShellRef}>
-        <div ref={mobileDirectionsRef}>
+      <div className="mobile-exercise-shell">
+        <div>
           <ExerciseDirectionsPanel />
         </div>
 
@@ -557,7 +492,7 @@ export default function ExercisePageClient({ params }: { params: Promise<{ id: s
             </button>
           </div>
 
-          <div className="mobile-workspace-panel" ref={mobileWorkspacePanelRef}>
+          <div className="mobile-workspace-panel">
             {activeMobileTab === 'source' && <SourcePanel showDescription={false} />}
             {activeMobileTab === 'viz' && (
               <ErrorBoundary>
@@ -576,7 +511,7 @@ export default function ExercisePageClient({ params }: { params: Promise<{ id: s
           </div>
         </section>
 
-        <div className="mobile-bottom-dock" ref={mobileBottomDockRef}>
+        <div className="mobile-bottom-dock">
           <ErrorBoundary>
             <InputPanel showToolkit={false} />
           </ErrorBoundary>
diff --git a/src/app/globals.css b/src/app/globals.css
index 90d9d76..bb56925 100644
--- a/src/app/globals.css
+++ b/src/app/globals.css
@@ -1021,10 +1021,8 @@ button.link-button:focus-visible,
 
   .mobile-workspace-panel {
     display: flex;
-    flex: 0 0 auto;
+    flex: 1 1 0%;
     flex-direction: column;
-    height: var(--mobile-workspace-panel-height, auto);
-    max-height: var(--mobile-workspace-panel-height, none);
     min-height: 0;
     overflow: hidden;
   }