If you dream or have a vision that it is night then this tells you about experiencing adversity and obstacles in reaching your goal, you have no clear view of you literally groping in the dark. Another explanation is that after a difficult period, there is an end through symbolic death or the end of a cycle followed by rebirth from a new beginning.
The night is a reflection of the transition between light and darkness (the gray life situation), death and rebirth. The stillness and movement that you experience in a situation and life. It also reflects that which is not yet visible, that which is not yet visible, patience everything appears at the right time. Alternatively, you can link the darkness to the galaxy, universe, alien or other dimensions.