Architectural lighting design is a special type of design that helps make buildings look pretty with lights. It is like when you play with the different colors on a paint palette to make a pretty picture.
In architectural lighting design, very smart people called lighting designers think about which lights to use, where to put them, and how bright or dim they should be. They also think about how the lights will help people see things, like stairs or doors, and how they will create special effects.
Some buildings use lots of different lights, and others only use a few. For example, a museum might use special lights that don't get too hot, so that the art won't get damaged. Lots of big buildings, like skyscrapers, also have different lights that help them stand out in the city at night.
So, next time you go for a walk at night, try to look at the buildings and see if you notice any cool lighting effects. That's probably because of the work of an architectural lighting designer!