diff --git a/src/components/dialog/header/SettingDialogHeader.vue b/src/components/dialog/header/SettingDialogHeader.vue
index 66765846f..ff172b5ab 100644
--- a/src/components/dialog/header/SettingDialogHeader.vue
+++ b/src/components/dialog/header/SettingDialogHeader.vue
@@ -15,9 +15,9 @@
 <script setup lang="ts">
 import Tag from 'primevue/tag'
 
-// Global variable from vite build defined in global.d.ts
-// eslint-disable-next-line no-undef
-const isStaging = !__USE_PROD_CONFIG__
+import { isProductionEnvironment } from '@/config/environment'
+
+const isStaging = !isProductionEnvironment()
 </script>
 
 <style scoped>
diff --git a/src/config/comfyApi.ts b/src/config/comfyApi.ts
index 272708264..35651d3df 100644
--- a/src/config/comfyApi.ts
+++ b/src/config/comfyApi.ts
@@ -1,7 +1,9 @@
-export const COMFY_API_BASE_URL = __USE_PROD_CONFIG__
+import { isProductionEnvironment } from './environment'
+
+export const COMFY_API_BASE_URL = isProductionEnvironment()
   ? 'https://api.comfy.org'
   : 'https://stagingapi.comfy.org'
 
-export const COMFY_PLATFORM_BASE_URL = __USE_PROD_CONFIG__
+export const COMFY_PLATFORM_BASE_URL = isProductionEnvironment()
   ? 'https://platform.comfy.org'
   : 'https://stagingplatform.comfy.org'
diff --git a/src/config/environment.ts b/src/config/environment.ts
new file mode 100644
index 000000000..70632235b
--- /dev/null
+++ b/src/config/environment.ts
@@ -0,0 +1,18 @@
+/**
+ * Runtime environment configuration that determines if we're in production or staging
+ * based on the hostname. Replaces the build-time __USE_PROD_CONFIG__ constant.
+ */
+
+/**
+ * Checks if the application is running in production environment
+ * @returns true if hostname is cloud.comfy.org (production), false otherwise (staging)
+ */
+export function isProductionEnvironment(): boolean {
+  // In SSR/Node.js environments or during build, use the environment variable
+  if (typeof window === 'undefined') {
+    return process.env.USE_PROD_CONFIG === 'true'
+  }
+
+  // In browser, check the hostname
+  return window.location.hostname === 'cloud.comfy.org'
+}
diff --git a/src/config/firebase.ts b/src/config/firebase.ts
index c3dc718a1..ed890bc6c 100644
--- a/src/config/firebase.ts
+++ b/src/config/firebase.ts
@@ -1,5 +1,7 @@
 import { FirebaseOptions } from 'firebase/app'
 
+import { isProductionEnvironment } from './environment'
+
 const DEV_CONFIG: FirebaseOptions = {
   apiKey: 'AIzaSyDa_YMeyzV0SkVe92vBZ1tVikWBmOU5KVE',
   authDomain: 'dreamboothy-dev.firebaseapp.com',
@@ -23,6 +25,6 @@ const PROD_CONFIG: FirebaseOptions = {
 }
 
 // To test with prod config while using dev server, set USE_PROD_CONFIG=true in .env
-export const FIREBASE_CONFIG: FirebaseOptions = __USE_PROD_CONFIG__
+export const FIREBASE_CONFIG: FirebaseOptions = isProductionEnvironment()
   ? PROD_CONFIG
   : DEV_CONFIG