diff --git a/src/components/LanguageToggle.tsx b/src/components/LanguageToggle.tsx
index 3a50883..86088b5 100644
--- a/src/components/LanguageToggle.tsx
+++ b/src/components/LanguageToggle.tsx
@@ -22,6 +22,8 @@ interface LanguageToggleProps {
   inline?: boolean;
   /** Additional class names */
   className?: string;
+  /** Called after a locale is chosen (e.g. to close a sheet sub-view). */
+  onSelect?: () => void;
   /** Variant style */
   variant?: 'default' | 'outline' | 'ghost';
 }
@@ -52,7 +54,7 @@ function Flag({ flag, className }: { flag: string; className?: string }) {
 /**
  * Language toggle dropdown for switching between the available locales
  */
-export function LanguageToggle({ compact = false, inline = false, className, variant = 'ghost' }: LanguageToggleProps) {
+export function LanguageToggle({ compact = false, inline = false, className, variant = 'ghost', onSelect }: LanguageToggleProps) {
   const { language, setLanguage, t } = useTranslation();
   const [query, setQuery] = useState('');
 
@@ -89,7 +91,7 @@ export function LanguageToggle({ compact = false, inline = false, className, var
           <button
             key={lang.code}
             type="button"
-            onClick={() => setLanguage(lang.code)}
+            onClick={() => { setLanguage(lang.code); onSelect?.(); }}
             className={cn(
               'flex items-center gap-3 rounded-xl px-4 py-3 text-left transition-all duration-200',
               language === lang.code
@@ -156,7 +158,7 @@ export function LanguageToggle({ compact = false, inline = false, className, var
         {filteredLanguages.map((lang) => (
           <DropdownMenuItem
             key={lang.code}
-            onClick={() => setLanguage(lang.code)}
+            onClick={() => { setLanguage(lang.code); onSelect?.(); }}
             className={cn(
               'flex min-h-11 items-center gap-3 cursor-pointer',
               language === lang.code && 'bg-primary/10 text-primary'
diff --git a/src/components/Layout.tsx b/src/components/Layout.tsx
index 6032d76..6e5714a 100644
--- a/src/components/Layout.tsx
+++ b/src/components/Layout.tsx
@@ -520,6 +520,9 @@ export function Layout({ children, noPadding }: LayoutProps) {
   const isFullBleed = noPadding || location.pathname === '/' || location.pathname === '/map';
   const [mobileMenuOpen, setMobileMenuOpen] = useState(false);
   const [mobileLanguageView, setMobileLanguageView] = useState(false);
+  // One auth dialog for the header + burger menu. Owning it here (not inside
+  // LoginArea) keeps it above the sheet and outside the sheet's unmount tree.
+  const [authDialog, setAuthDialog] = useState<'login' | 'signup' | null>(null);
   const [showStatusDialog, setShowStatusDialog] = useState(false);
   const [showCustomizeNav, setShowCustomizeNav] = useState(false);
   const [showAddAccount, setShowAddAccount] = useState(false);
@@ -537,15 +540,28 @@ export function Layout({ children, noPadding }: LayoutProps) {
     try { sessionStorage.setItem(WELCOME_LOGIN_SNOOZED, '1'); } catch { /* ignore */ }
     setShowWelcomeLogin(false);
   };
+  const requestAuth = (kind: 'login' | 'signup') => {
+    // Close every overlay that owns a lower z-index before opening the auth
+    // dialog. The burger sheet is z-2100; a dialog rendered inside it is z-50
+    // and becomes invisible/unclickable.
+    try { sessionStorage.setItem(WELCOME_LOGIN_SNOOZED, '1'); } catch { /* ignore */ }
+    setMobileMenuOpen(false);
+    setMobileLanguageView(false);
+    setShowWelcomeLogin(false);
+    setShowWelcomeSignup(false);
+    setAuthDialog(kind);
+  };
+  const requestLogin = () => requestAuth('login');
+  const requestSignup = () => requestAuth('signup');
   useEffect(() => {
-    if (user || isNativePlatform()) return;
+    if (user || authDialog || isNativePlatform()) return;
     try {
       if (sessionStorage.getItem(WELCOME_LOGIN_SNOOZED) === '1') return;
     } catch { return; }
     if (typeof window === 'undefined' || !window.matchMedia?.('(min-width: 1024px)').matches) return;
     const timer = window.setTimeout(() => setShowWelcomeLogin(true), 900);
     return () => window.clearTimeout(timer);
-  }, [user]);
+  }, [user, authDialog]);
   const { t, language } = useTranslation();
   const currentLanguage = LANGUAGE_OPTIONS.find((item) => item.code === language) ?? LANGUAGE_OPTIONS[0];
   const { currentUser: currentAccount, removeLogin } = useLoggedInAccounts();
@@ -786,7 +802,7 @@ export function Layout({ children, noPadding }: LayoutProps) {
                 <Settings className="h-5 w-5" />
               </Button>
             </Link>
-            <LoginArea className="max-w-60" />
+            <LoginArea className="max-w-60" onLoginRequest={requestLogin} onSignupRequest={requestSignup} />
           </div>
         </div>
       </header>
@@ -827,7 +843,7 @@ export function Layout({ children, noPadding }: LayoutProps) {
               />
             )}
             <div className={cn(user && 'hidden')}>
-              <LoginArea compact className="flex flex-row gap-1" />
+              <LoginArea compact className="flex flex-row gap-1" onLoginRequest={requestLogin} onSignupRequest={requestSignup} />
             </div>
             
             <Sheet
@@ -857,7 +873,7 @@ export function Layout({ children, noPadding }: LayoutProps) {
                       <h2 className="text-xl font-black uppercase tracking-wide">
                         {t('settings.selectLanguage')}
                       </h2>
-                      <LanguageToggle inline className="mt-3 w-full" variant="ghost" />
+                      <LanguageToggle inline className="mt-3 w-full" variant="ghost" onSelect={() => setMobileLanguageView(false)} />
                     </div>
                   </div>
                 ) : (
@@ -1102,7 +1118,7 @@ export function Layout({ children, noPadding }: LayoutProps) {
                           <p className="text-sm text-muted-foreground mb-4">
                             {t('chromeUi.loggedOutPrompt')}
                           </p>
-                          <LoginArea className="w-full justify-center" />
+                          <LoginArea className="w-full justify-center" onLoginRequest={requestLogin} onSignupRequest={requestSignup} />
                         </div>
                       </>
                     )}
@@ -1256,6 +1272,24 @@ export function Layout({ children, noPadding }: LayoutProps) {
         />
       </Suspense>
 
+      {/* Header/burger auth — owned here so closing the sheet cannot unmount it
+          and it always sits above the sheet + welcome overlay. */}
+      <Suspense fallback={null}>
+        <LazyLoginDialog
+          isOpen={authDialog === 'login'}
+          onClose={() => setAuthDialog(null)}
+          onLogin={() => setAuthDialog(null)}
+          onSignup={() => setAuthDialog('signup')}
+        />
+      </Suspense>
+      <Suspense fallback={null}>
+        <LazySignupDialog
+          isOpen={authDialog === 'signup'}
+          onClose={() => setAuthDialog(null)}
+          onUseAmber={() => setAuthDialog('login')}
+        />
+      </Suspense>
+
       {/* Newsletter: floating pill + Monday admin reminder */}
       <NewsletterOverlay />
 
diff --git a/src/components/auth/LoginArea.tsx b/src/components/auth/LoginArea.tsx
index c231f41..87735d1 100644
--- a/src/components/auth/LoginArea.tsx
+++ b/src/components/auth/LoginArea.tsx
@@ -15,14 +15,31 @@ export interface LoginAreaProps {
   className?: string;
   /** Compact mode for mobile headers - smaller buttons without text */
   compact?: boolean;
+  /**
+   * Open auth in a caller-owned dialog instead of this component's local one.
+   * The mobile burger sheet uses this: its local dialog would portal *behind*
+   * the sheet (z-50 vs z-2100) and leave the menu looking stuck.
+   */
+  onLoginRequest?: () => void;
+  onSignupRequest?: () => void;
 }
 
-export function LoginArea({ className, compact }: LoginAreaProps) {
+export function LoginArea({ className, compact, onLoginRequest, onSignupRequest }: LoginAreaProps) {
   const { currentUser } = useLoggedInAccounts();
   const { t } = useTranslation();
   const [loginDialogOpen, setLoginDialogOpen] = useState(false);
   const [signupDialogOpen, setSignupDialogOpen] = useState(false);
 
+  const globalAuth = !!onLoginRequest && !!onSignupRequest;
+  const openLogin = () => {
+    if (onLoginRequest) onLoginRequest();
+    else setLoginDialogOpen(true);
+  };
+  const openSignup = () => {
+    if (onSignupRequest) onSignupRequest();
+    else setSignupDialogOpen(true);
+  };
+
   const handleLogin = () => {
     setLoginDialogOpen(false);
     setSignupDialogOpen(false);
@@ -31,12 +48,12 @@ export function LoginArea({ className, compact }: LoginAreaProps) {
   return (
     <div className={cn("inline-flex items-center justify-center", className)}>
       {currentUser ? (
-        <AccountSwitcher onAddAccountClick={() => setLoginDialogOpen(true)} />
+        <AccountSwitcher onAddAccountClick={openLogin} />
       ) : compact ? (
         // Compact mode for mobile headers - icon only
         <div className="flex gap-1 justify-center">
           <Button
-            onClick={() => setSignupDialogOpen(true)}
+            onClick={openSignup}
             size="icon"
             className='h-9 w-9 rounded-full bg-[#ccff00] text-black hover:bg-[#ccff00]/90'
             title={t('settingsUi.loginArea.signUp')}
@@ -44,7 +61,7 @@ export function LoginArea({ className, compact }: LoginAreaProps) {
             <UserPlus className='w-4 h-4' />
           </Button>
           <Button
-            onClick={() => setLoginDialogOpen(true)}
+            onClick={openLogin}
             variant="outline"
             size="icon"
             className="h-9 w-9 rounded-full border border-gray-600 hover:border-[#ff0040]"
@@ -57,14 +74,14 @@ export function LoginArea({ className, compact }: LoginAreaProps) {
         // Default full-size buttons
         <div className="flex gap-3 justify-center w-full">
           <Button
-            onClick={() => setSignupDialogOpen(true)}
+            onClick={openSignup}
             className='flex items-center gap-2 px-5 py-2.5 rounded-full bg-[#ccff00] text-black hover:bg-[#ccff00]/90 font-bold transition-all flex-1 sm:flex-none'
           >
             <UserPlus className='w-4 h-4' />
             <span>{t('settingsUi.loginArea.signUp')}</span>
           </Button>
           <Button
-            onClick={() => setLoginDialogOpen(true)}
+            onClick={openLogin}
             variant="outline"
             className="flex items-center gap-2 px-5 py-2.5 rounded-full font-medium transition-all border-2 border-gray-600 hover:border-[#ff0040] flex-1 sm:flex-none"
           >
@@ -74,24 +91,31 @@ export function LoginArea({ className, compact }: LoginAreaProps) {
         </div>
       )}
 
-      <LoginDialog
-        isOpen={loginDialogOpen}
-        onClose={() => setLoginDialogOpen(false)}
-        onLogin={handleLogin}
-        onSignup={() => setSignupDialogOpen(true)}
-      />
+      {!globalAuth && (
+        <>
+          <LoginDialog
+            isOpen={loginDialogOpen}
+            onClose={() => setLoginDialogOpen(false)}
+            onLogin={handleLogin}
+            onSignup={() => {
+              setLoginDialogOpen(false);
+              setSignupDialogOpen(true);
+            }}
+          />
 
-      {/* One signup entry point. The old "Recovery Phrase vs Secret Key" method
-          chooser was dead code (never opened) and pure jargon for a newcomer —
-          SignupDialog owns the whole flow now. */}
-      <SignupDialog
-        isOpen={signupDialogOpen}
-        onClose={() => setSignupDialogOpen(false)}
-        onUseAmber={() => {
-          setSignupDialogOpen(false);
-          setLoginDialogOpen(true);
-        }}
-      />
+          {/* One signup entry point. The old "Recovery Phrase vs Secret Key"
+              method chooser was dead code (never opened) and pure jargon for a
+              newcomer — SignupDialog owns the whole flow now. */}
+          <SignupDialog
+            isOpen={signupDialogOpen}
+            onClose={() => setSignupDialogOpen(false)}
+            onUseAmber={() => {
+              setSignupDialogOpen(false);
+              setLoginDialogOpen(true);
+            }}
+          />
+        </>
+      )}
     </div>
   );
 }
\ No newline at end of file
diff --git a/src/components/auth/LoginDialog.tsx b/src/components/auth/LoginDialog.tsx
index 622ddeb..2caa40e 100644
--- a/src/components/auth/LoginDialog.tsx
+++ b/src/components/auth/LoginDialog.tsx
@@ -321,7 +321,7 @@ export const LoginDialog: React.FC<LoginDialogProps> = ({ isOpen, onClose, onLog
 
   return (
     <Dialog open={isOpen} onOpenChange={onClose}>
-      <DialogContent className={cn("flex w-[calc(100%-1rem)] flex-col sm:max-w-md max-h-[calc(100dvh-2rem)] p-0 overflow-hidden rounded-2xl bg-black border-2 border-[#ff0040]/50")}>
+      <DialogContent className={cn("z-[2200] flex w-[calc(100%-1rem)] flex-col sm:max-w-md max-h-[calc(100dvh-2rem)] p-0 overflow-hidden rounded-2xl bg-black border-2 border-[#ff0040]/50")}>
         <DialogHeader className={cn('px-5 pt-5 pb-3')}>
           <DialogTitle className="text-center font-black uppercase tracking-wide text-lg">
             {t('settingsUi.loginDialog.welcomeTitle')}
diff --git a/src/components/auth/SignupDialog.tsx b/src/components/auth/SignupDialog.tsx
index cdcde83..da8644a 100644
--- a/src/components/auth/SignupDialog.tsx
+++ b/src/components/auth/SignupDialog.tsx
@@ -375,7 +375,7 @@ const SignupDialog: React.FC<SignupDialogProps> = ({ isOpen, onClose, onComplete
   return (
     <Dialog open={isOpen} onOpenChange={onClose}>
       <DialogContent
-        className={cn("w-[calc(100%-1rem)] sm:max-w-md max-h-[90vh] max-h-[90dvh] p-0 overflow-hidden rounded-2xl flex flex-col")}
+        className={cn("z-[2200] w-[calc(100%-1rem)] sm:max-w-md max-h-[90vh] max-h-[90dvh] p-0 overflow-hidden rounded-2xl flex flex-col")}
       >
         <DialogHeader className={cn('px-4 sm:px-6 pt-4 sm:pt-6 pb-1 relative flex-shrink-0')}>
           <DialogTitle className={cn('font-semibold text-center text-base sm:text-lg')}>