diff --git a/backend/app/api/designs.py b/backend/app/api/designs.py
index d908234..001045a 100644
--- a/backend/app/api/designs.py
+++ b/backend/app/api/designs.py
@@ -23,7 +23,7 @@ settings = get_settings()
 MOCKUP_TEMPLATES = {
     "shirt": {
         "template": "shirt-template.png",
-        "design_box": (330, 310, 370, 370),  # x, y, w, h — chest area on black tee
+        "design_box": (262, 230, 500, 450),  # x, y, w, h — chest area on black tee
         "blend": "screen",  # screen blend for light designs on dark fabric
     },
     "sticker": {
diff --git a/frontend/lib/mockups.ts b/frontend/lib/mockups.ts
index 84534b4..2f4a6c6 100644
--- a/frontend/lib/mockups.ts
+++ b/frontend/lib/mockups.ts
@@ -12,7 +12,7 @@ export interface MockupConfig {
 export const MOCKUP_CONFIGS: MockupConfig[] = [
   {
     template: "/mockups/shirt-template.png",
-    designArea: { x: 330, y: 310, width: 370, height: 370 },
+    designArea: { x: 262, y: 230, width: 500, height: 450 },
     label: "T-Shirt",
     productType: "shirt",
     price: 29.99,