Why would turning off all the lights at night keep Bruno's family safe?

Turning off all the lights at night can keep Bruno's family safe by reducing visibility from the outside, making it harder for potential intruders to see into their home. It also minimizes the risk of attracting attention from passersby, ensuring that their activities remain discreet. Additionally, in a context where they might be in danger or under threat, such as during a time of conflict, darkness can provide a sense of security by helping them blend into their surroundings.