diff --git a/nginx/prod-proxy.conf b/nginx/prod-proxy.conf
index 165e952..3224bab 100644
--- a/nginx/prod-proxy.conf
+++ b/nginx/prod-proxy.conf
@@ -1,5 +1,12 @@
 # 正式環境 (Production) - 端口 80
 # 外部 SSL 終止後（如 Cloudflare/NPM）轉發至此端口
+
+# 定義 map 以正確處理 X-Forwarded-Proto
+map $http_x_forwarded_proto $proxy_x_forwarded_proto {
+    default $http_x_forwarded_proto;
+    ''      $scheme;
+}
+
 server {
     listen 80;
     server_name erp.koori.tw erp.mamaiclub.com;
@@ -9,7 +16,7 @@ server {
         proxy_set_header Host $host;
         proxy_set_header X-Real-IP $remote_addr;
         proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
-        proxy_set_header X-Forwarded-Proto $scheme;
+        proxy_set_header X-Forwarded-Proto $proxy_x_forwarded_proto;
         proxy_set_header X-Forwarded-Host $host;
     }
 }