diff --git a/vessel/src/app/page.tsx b/vessel/src/app/page.tsx
index 5dcff4717..c194619fe 100644
--- a/vessel/src/app/page.tsx
+++ b/vessel/src/app/page.tsx
@@ -7455,7 +7455,7 @@ export default function App() {
           guidedDesktopComposerDock
             ? "gap-0 p-4 pb-56"
             : guidedMobileComposerDock
-              ? "gap-5 px-4 pt-5 pb-[var(--guided-mobile-composer-reserve)] sm:px-5"
+              ? "gap-5 px-4 pt-5 pb-40 sm:px-5"
               : "gap-0 p-4",
         )}
       >
@@ -7508,7 +7508,7 @@ export default function App() {
           "relative shrink-0 pointer-events-auto backdrop-blur-md",
           sessionActive && "animate-chat-composer-pulse",
           guidedMobileComposerDock
-            ? "fixed inset-x-0 bottom-0 z-[80] bg-drift-canvas/95 p-0 shadow-[0_-18px_45px_rgba(2,6,14,0.72)]"
+            ? "fixed inset-x-0 bottom-[calc(4.5rem+env(safe-area-inset-bottom,0px))] z-[80] bg-drift-canvas/95 p-0 shadow-[0_-18px_45px_rgba(2,6,14,0.72)]"
             : "border-t border-slate-900 bg-[#07090e]/95 p-3",
           guidedDesktopComposerDock && "shadow-[0_-12px_32px_rgba(2,6,14,0.55)]",
           guidedMobileComposerDock && !sessionActive && "pb-[max(0.25rem,env(safe-area-inset-bottom))]",
@@ -8081,7 +8081,7 @@ export default function App() {
         return (
           <div className={cn(
             "flex flex-col h-full overflow-y-auto p-6",
-            guidedMobileComposerDock && "pb-[var(--guided-mobile-composer-reserve)]",
+            guidedMobileComposerDock && "pb-40",
           )}>
             <button
               onClick={() => setShowFullCardInActiveSession(false)}
@@ -8623,7 +8623,7 @@ export default function App() {
             </div>
 
             {/* Welcome panel body */}
-            <div className={cn("flex-1 min-h-0 overflow-y-auto", guidedMobileComposerDock && "pb-[var(--guided-mobile-composer-reserve)]")}>
+            <div className={cn("flex-1 min-h-0 overflow-y-auto", guidedMobileComposerDock && "pb-40")}>
               {renderGuidedRightPanel()}
             </div>
 
@@ -8666,7 +8666,7 @@ export default function App() {
         return (
           <div className={cn(
             "flex flex-col h-dvh w-full bg-transparent text-slate-100 overflow-y-auto p-6 relative z-10",
-            guidedMobileComposerDock ? "pb-[var(--guided-mobile-composer-reserve)]" : "pb-24",
+            guidedMobileComposerDock ? "pb-40" : "pb-24",
           )}>
             <div className="mb-6 flex items-center justify-between gap-3">
               <button
@@ -8757,7 +8757,7 @@ export default function App() {
               </div>
             </div>
 
-            <div className="flex flex-col flex-1 min-h-0 overflow-hidden pb-[var(--guided-mobile-composer-reserve)]">
+            <div className="flex flex-col flex-1 min-h-0 overflow-hidden pb-40">
               <div className="flex min-h-0 flex-1 flex-col overflow-hidden">
                 {latestReadingText && latestReadingId && (
                   <div className="shrink-0 border-b border-cyan-500/15 bg-[#07090e]/80 px-4 py-2.5 backdrop-blur-sm">
@@ -10051,7 +10051,7 @@ export default function App() {
         </div>
       )}
 
-      {isCompactViewport && !guidedMobileComposerDock && <SurfaceMobileSubnav current="chat" />}
+      {isCompactViewport && <SurfaceMobileSubnav current="chat" />}
 
       {renderGuidedView()}
       {renderGuidedPersistentComposerDock()}
diff --git a/vessel/src/test/api-smoke.test.ts b/vessel/src/test/api-smoke.test.ts
index 1e40fb8b2..556e2f6bb 100644
--- a/vessel/src/test/api-smoke.test.ts
+++ b/vessel/src/test/api-smoke.test.ts
@@ -4269,12 +4269,12 @@ test('alignment corridor primes on request dispatch instead of generic loading s
     assert.ok(pageSource.includes('mobileComposerDock={guidedMobileComposerDock}'));
     assert.ok(pageSource.includes('data-guided-mobile-composer-anchor={guidedMobileComposerDock ? "true" : undefined}'));
     assert.ok(pageSource.includes('data-guided-persistent-composer="true"'));
-    assert.ok(pageSource.includes('fixed inset-x-0 bottom-0 z-[80]'));
+    assert.ok(pageSource.includes('fixed inset-x-0 bottom-[calc(4.5rem+env(safe-area-inset-bottom,0px))] z-[80]'));
     assert.ok(pageSource.includes('ResizeObserver'));
     assert.ok(pageSource.includes('GUIDED_MOBILE_COMPOSER_MIN_RESERVE_PX'));
     assert.ok(pageSource.includes('--guided-mobile-composer-reserve'));
-    assert.ok(pageSource.includes('pb-[var(--guided-mobile-composer-reserve)]'));
-    assert.ok(pageSource.includes('isCompactViewport && !guidedMobileComposerDock && <SurfaceMobileSubnav current="chat" />'));
+    assert.ok(pageSource.includes('pb-40'));
+    assert.ok(pageSource.includes('isCompactViewport && <SurfaceMobileSubnav current="chat" />'));
     assert.ok(chatInputSource.includes('mobileComposerDock?: boolean'));
     assert.ok(chatInputSource.includes('data-chatinput-mobile-dock="true"'));
     assert.ok(chatInputSource.includes('z-30 border-t border-white'));
diff --git a/vessel/src/test/mobile-chat-layout.test.ts b/vessel/src/test/mobile-chat-layout.test.ts
index 682de75cd..2aa4532cf 100644
--- a/vessel/src/test/mobile-chat-layout.test.ts
+++ b/vessel/src/test/mobile-chat-layout.test.ts
@@ -8,10 +8,10 @@ test('mobile chat reserves measured composer space and exposes surface shortcuts
   assert.match(pageSource, /GUIDED_MOBILE_COMPOSER_MIN_RESERVE_PX/);
   assert.match(pageSource, /ResizeObserver/);
   assert.match(pageSource, /--guided-mobile-composer-reserve/);
-  assert.match(pageSource, /pb-\[var\(--guided-mobile-composer-reserve\)\]/);
+  assert.match(pageSource, /pb-40/);
   assert.match(pageSource, /data-guided-orientation-home/);
   assert.match(pageSource, /guidedMobileComposerDock \? "min-h-0" : "h-full justify-between"/);
-  assert.match(pageSource, /isCompactViewport && !guidedMobileComposerDock && <SurfaceMobileSubnav current="chat" \/>/);
+  assert.match(pageSource, /isCompactViewport && <SurfaceMobileSubnav current="chat" \/>/);
   assert.match(pageSource, /SURFACE_NAV\.planner/);
   assert.match(pageSource, /SURFACE_NAV\.astroPages/);
   assert.match(pageSource, /SURFACE_NAV\.plans/);