anchor.diff:    return maximizeRect;
   }
   
  +/// Return the bounding box for the minimize button.
   Pointer<RECT> getMinimizeRect(int hwnd, Pointer<RECT> titleBarRect) {
     final dpi = GetDpiForWindow(hwnd);
     final buttonWidth = dpiScale(47, dpi);
  
positive.code:   final paddingX = (parentWidth - childWidth) ~/ 2;
    final paddingY = (parentHeight - childHeight) ~/ 2;
  
    child.ref.left = parent.ref.left + paddingX;
    child.ref.top = parent.ref.top + paddingY;
    child.ref.right = child.ref.left + childWidth;
    child.ref.bottom = child.ref.top + childHeight;
  }
  
  int mainWindowProc(int hwnd, int msg, int wParam, int lParam) {
    final hoveredButton = GetWindowLongPtr(hwnd, GWLP_USERDATA);
  
    switch (msg) {
      case WM_NCCALCSIZE:
        // Handling this event allows us to extend the client (paintable) area
        // into the title bar region.
        //
        // Per https://docs.microsoft.com/en-us/windows/win32/dwm/customframe:
        //
        // "To remove the standard window frame, you must handle the WM_NCCALCSIZE
        // message, specifically when its wParam value is TRUE and the return
        // value is 0. By doing so, your application uses the entire window region
        // as the client area, removing the standard frame."
        if (wParam == 0) return DefWindowProc(hwnd, msg, wParam, lParam);
        final dpi = GetDpiForWindow(hwnd);
  
        final frameX = GetSystemMetricsForDpi(SM_CXFRAME, dpi);
  
negative.code:     ..ref.cbSize = sizeOf<WNDCLASSEX>()
      ..ref.lpszClassName = windowClassName
      ..ref.style = CS_HREDRAW | CS_VREDRAW
      ..ref.hCursor = LoadCursor(NULL, IDC_ARROW)
      ..ref.lpfnWndProc = Pointer.fromFunction<WindowProc>(mainWindowProc, 0);
  
    RegisterClassEx(windowClass);
  