diff --git a/VideoPlayerForm.cs b/VideoPlayerForm.cs
index d4c2775..0f1dd95 100644
--- a/VideoPlayerForm.cs
+++ b/VideoPlayerForm.cs
@@ -399,7 +399,7 @@ namespace DualScreenDemo
                 throw; // Rethrow the exception to handle it further up the call stack
             }
         }
-
+        // 同步畫面事件
         public void SyncToPrimaryMonitor()
         {
             PrimaryForm.Instance.primaryScreenPanel.Visible = true;
@@ -441,11 +441,35 @@ namespace DualScreenDemo
                     // Console.WriteLine("VMR9 is not initialized.");
                     return;
                 }
+                int designWidth = 1620;
+                int designHeight = 1080;
 
+                int actualWidth = PrimaryForm.Instance.primaryScreenPanel.Width;
+                int actualHeight = PrimaryForm.Instance.primaryScreenPanel.Height;
+
+                // 等比例縮放（不會超出，fit）
+                float scaleX = (float)actualWidth / designWidth;
+                float scaleY = (float)actualHeight / designHeight;
+                float scale = Math.Min(scaleX, scaleY);
+
+                // 計算縮放後的尺寸（但起點仍是 0,0）
+                int newWidth = (int)(designWidth * scale);
+                int newHeight = (int)(designHeight * scale);
+                
+                // trash location with trash flexible of screen size.
+                if (actualWidth == 1024){
+                    newWidth = (int)(newWidth * 0.84f);
+                }
+                else if (actualWidth == 1440){
+                    newWidth = (int)(newWidth * 0.9f);
+                }
                 videoWindowPrimary = (IVideoWindow)videoRendererPrimary;
-                videoWindowPrimary.put_Owner(PrimaryForm.Instance.primaryScreenPanel.Handle); // 设置为 primaryScreenPanel 的句柄
+                videoWindowPrimary.put_Owner(PrimaryForm.Instance.primaryScreenPanel.Handle);
                 videoWindowPrimary.put_WindowStyle(WindowStyle.Child | WindowStyle.ClipChildren);
-                videoWindowPrimary.SetWindowPosition(0, 0, 1620, 1080); // 调整视频窗口大小以填满黑色区域
+
+                // ⬅ 左上角對齊（固定從 0,0 開始）
+                videoWindowPrimary.SetWindowPosition(0, 0, newWidth, newHeight);
+
                 videoWindowPrimary.put_Visible(OABool.True);
 
                 // Console.WriteLine("Video window configured successfully.");