diff --git a/apps/api/src/lib/auth.ts b/apps/api/src/lib/auth.ts
index 8e90768..11acfd8 100644
--- a/apps/api/src/lib/auth.ts
+++ b/apps/api/src/lib/auth.ts
@@ -28,14 +28,26 @@ function hashToken(token: string) {
   return createHash('sha256').update(`${env.sessionSecret}:${token}`).digest('hex');
 }
 
-export function createSessionCookie(token: string) {
+function isSecureRequest(headers?: { get(name: string): string | null }) {
+  if (env.secureCookies) return true;
+  // Detect HTTPS behind proxy (X-Forwarded-Proto)
+  const proto = headers?.get('x-forwarded-proto');
+  if (proto === 'https') return true;
+  return false;
+}
+
+function buildSameSite(headers?: { get(name: string): string | null }) {
+  return isSecureRequest(headers) ? 'SameSite=None; Secure' : 'SameSite=Lax';
+}
+
+export function createSessionCookie(token: string, headers?: { get(name: string): string | null }) {
   const maxAge = 60 * 60 * 24 * 30;
-  const sameSite = env.secureCookies ? 'SameSite=None; Secure' : 'SameSite=Lax';
+  const sameSite = buildSameSite(headers);
   return `${sessionCookieName}=${token}; HttpOnly; Path=/; ${sameSite}; Max-Age=${maxAge}`;
 }
 
-export function clearSessionCookie() {
-  const sameSite = env.secureCookies ? 'SameSite=None; Secure' : 'SameSite=Lax';
+export function clearSessionCookie(headers?: { get(name: string): string | null }) {
+  const sameSite = buildSameSite(headers);
   return `${sessionCookieName}=; HttpOnly; Path=/; ${sameSite}; Max-Age=0`;
 }
 
diff --git a/apps/api/src/routes/auth.ts b/apps/api/src/routes/auth.ts
index 770d1e5..cb60458 100644
--- a/apps/api/src/routes/auth.ts
+++ b/apps/api/src/routes/auth.ts
@@ -38,7 +38,7 @@ export const authRoutes = new Elysia({ prefix: '/api/v1/auth' })
       features: getAuthFeatures(),
     };
   })
-  .post('/register', async ({ body, set }) => {
+  .post('/register', async ({ body, set, request }) => {
     const req = body as Partial<RegisterRequest> | undefined;
     const email = normalizeEmail(req?.email);
     const name = normalizeName(req?.name);
@@ -62,7 +62,7 @@ export const authRoutes = new Elysia({ prefix: '/api/v1/auth' })
 
       const user = inserted[0];
       const token = await createSession(user.id);
-      set.headers['Set-Cookie'] = createSessionCookie(token);
+      set.headers['Set-Cookie'] = createSessionCookie(token, request.headers);
 
       authCounter.labels('register', 'true').inc();
 
@@ -79,7 +79,7 @@ export const authRoutes = new Elysia({ prefix: '/api/v1/auth' })
       return serviceUnavailable('Database unavailable');
     }
   })
-  .post('/login', async ({ body, set }) => {
+  .post('/login', async ({ body, set, request }) => {
     const req = body as Partial<AuthRequest> | undefined;
     const email = normalizeEmail(req?.email);
 
@@ -98,7 +98,7 @@ export const authRoutes = new Elysia({ prefix: '/api/v1/auth' })
       }
 
       const token = await createSession(user.id);
-      set.headers['Set-Cookie'] = createSessionCookie(token);
+      set.headers['Set-Cookie'] = createSessionCookie(token, request.headers);
 
       authCounter.labels('login', 'true').inc();
 
@@ -116,8 +116,9 @@ export const authRoutes = new Elysia({ prefix: '/api/v1/auth' })
     }
   })
   .post('/logout', async ({ request, set }) => {
-    await deleteSession(readSessionToken(request.headers.get('cookie')));
-    set.headers['Set-Cookie'] = clearSessionCookie();
+    const cookieHeader = request.headers.get('cookie');
+    await deleteSession(readSessionToken(cookieHeader));
+    set.headers['Set-Cookie'] = clearSessionCookie(request.headers);
     return { ok: true };
   })
   .get('/google', ({ set }) => {
diff --git a/apps/web/src/components/auth-guard.tsx b/apps/web/src/components/auth-guard.tsx
index ed4ac06..ed76d53 100644
--- a/apps/web/src/components/auth-guard.tsx
+++ b/apps/web/src/components/auth-guard.tsx
@@ -10,27 +10,32 @@ type AuthGuardProps = {
 };
 
 export function AuthGuard({ children, requireExpert = false }: AuthGuardProps) {
+  const user = useAuthStore((state) => state.user);
   const setUser = useAuthStore((state) => state.setUser);
   const query = useQuery({
     queryKey: ['auth', 'me'],
     queryFn: () => apiClient.getMe(),
+    staleTime: 30_000,
   });
 
   useEffect(() => {
-    if (query.data) {
+    if (query.data?.user) {
       setUser(query.data.user);
     }
   }, [query.data, setUser]);
 
-  if (query.isLoading) {
+  // Tunjukkan loading hanya jika belum ada user di store
+  if (query.isLoading && !user) {
     return <main className="min-h-screen p-8 text-center text-muted-foreground">Memeriksa sesi...</main>;
   }
 
-  if (!query.data?.user) {
+  // Cek store dulu, baru query — mencegah redirect saat refetch background
+  const currentUser = query.data?.user ?? user;
+  if (!currentUser) {
     return <Navigate to="/login" replace />;
   }
 
-  if (requireExpert && query.data.user.role !== 'expert') {
+  if (requireExpert && currentUser.role !== 'expert') {
     return <Navigate to="/dashboard" replace />;
   }
 
diff --git a/apps/web/src/components/auth-initializer.tsx b/apps/web/src/components/auth-initializer.tsx
index 765408a..a5239ac 100644
--- a/apps/web/src/components/auth-initializer.tsx
+++ b/apps/web/src/components/auth-initializer.tsx
@@ -9,6 +9,7 @@ export function AuthInitializer() {
     queryKey: ['auth', 'me'],
     queryFn: () => apiClient.getMe(),
     retry: false,
+    staleTime: 30_000,
   });
 
   useEffect(() => {