It might have buildings with a lot of greenery incorporated into them. For example, the walls could be covered in vines or other plants that blend in with the surrounding jungle. There could be tall, tree - like structures that serve as both support and living spaces, with platforms at different levels like the branches of a tree.
Architecturally, such a city could feature buildings with sloped roofs to deal with the heavy rain common in jungles. The roofs might be made of materials that can quickly drain water and are resistant to the growth of moss and other jungle plants. There could also be large open - air spaces within the buildings, like atriums filled with jungle plants, to create a connection between the inside and outside of the structures.
The city in jungle science fiction would likely have a unique blend of modern and natural elements in its architecture. Some buildings could be built around large, ancient trees, using the trees as part of the structure. There might be bridges made of natural materials like vines and bamboo, connecting different parts of the city. And the overall layout might be more spread out and less grid - like compared to normal cities, following the natural contours of the jungle terrain.