下沉式街道庭院效果

Quick answer：

The term 'sunken street courtyard effect' refers to a design concept in urban planning where a courtyard or open space is situated below the level of the surrounding streets. This creates a unique microclimate, offering a quiet, serene atmosphere away from the hustle and bustle of the city. The design often includes features like stepped terraces, water features, and lush greenery to enhance the aesthetic and functional aspects of the space.