diff --git a/py-kivy/API.md b/py-kivy/API.md
index 69316ef..5ce3036 100644
--- a/py-kivy/API.md
+++ b/py-kivy/API.md
@@ -532,3 +532,39 @@ Error response body:
   "detail": "Error message"
 }
 ```
+
+```mermaid
+graph TD
+    A[API v1] --> B[Authentication]
+    A --> C[Items]
+    A --> D[Orders]
+    A --> E[Users]
+
+    B --> B1["POST /token"]
+
+    C --> C1["POST /items"]
+    C --> C2["GET /items"]
+    C --> C3["GET /items/:item_id"]
+    C --> C4["PUT /items/:item_id"]
+    C --> C5["DELETE /items/:item_id"]
+
+    D --> D1["POST /orders"]
+    D --> D2["GET /orders"]
+    D --> D3["GET /orders/:order_id"]
+    D --> D4["PUT /orders/:order_id"]
+    D --> D5["DELETE /orders/:order_id"]
+    D --> D6["POST /orders/:order_id/process_payment"]
+    D --> D7["POST /orders/:order_id/apply_discount"]
+
+    E --> E1["POST /users"]
+    E --> E2["GET /users/me"]
+    E --> E3["GET /users"]
+    E --> E4["PUT /users/:user_id"]
+    E --> E5["DELETE /users/:user_id"]
+
+    class A main;
+    class B auth;
+    class C items;
+    class D orders;
+    class E users;
+```
diff --git a/py-kivy/DESIGN-DOC.md b/py-kivy/DESIGN-DOC.md
index 61b172e..dd207c0 100644
--- a/py-kivy/DESIGN-DOC.md
+++ b/py-kivy/DESIGN-DOC.md
@@ -82,6 +82,8 @@ The POS System is a cross-platform application built using Python, FastAPI for t
 
 ### 4.1 Layout
 
+![A Mockup](mockup-1.png)
+
 - Responsive design for various screen sizes
 - Left navigation bar (collapsible)
 - Main content area (grid/list views)
diff --git a/py-kivy/mockup-1.png b/py-kivy/mockup-1.png
new file mode 100644
index 0000000..422f1ae
Binary files /dev/null and b/py-kivy/mockup-1.png differ