How can I change the border color in LibreOffice base

In my report from LibreOffice base I want a square with no filling and with black borders… Is this possible? I tried with a form with no success… and with a frame ( could not change the thickness )

Hello,

The only semi-success in the past on Report Builder was to create one using lines. A real pain and hard to get it to look even semi decent.

Thank you for your answer!