How to get/ change the color of a Systemcolor

procedure TForm1.Button1Click(Sender: TObject);
var
  SysColor: DWORD;
  Kind: Integer;
  Color: TColor;
begin

  // Get the clBtnFace Color with the GetSysColor function:

  SysColor := GetSysColor(COLOR_BTNFACE);
  // Show the Color-Constant, Farbe-Konstante anzeigen
  ShowMessage(ColorToString(TColor(SysColor)));
  // Show the Hex-Value, Hexadezimal-Wert anzeigen
  ShowMessage(IntToHex((SysColor), 8));


  // clBtnFace Farbe ohne GetSysColor ermitteln:

  // Show the Color-Constant, Farbe-Konstante anzeigen
  ShowMessage(ColorToString(ColorToRGB(clBtnFace)));
  // Show the Hex-Value, Hexadezimal-Wert anzeigen
  ShowMessage(IntToHex(ColorToRGB(clBtnFace), 8));

  // Changing a Systemcolor with SetSysColors:

  Kind  := COLOR_BTNFACE; // Color to change, Zu wechselnde Farbe
  Color := ClRed; // New Color, neue Farbe
  SetSysColors(Kind, Kind, Color);
end;