Use light-colored wood for the square  pergola to keep a natural and modern aesthetic. Add a geometric pattern to the square  pergola's roof for visual interest. Ensure the bar has a sleek and contemporary design, with a menu board and counter. Place comfortable and stylish seating options like armchairs and couches. Incorporate greenery around the seating area, including planters and potted plants. Design the floor with natural materials like wood or stone to match the square  pergola. Include ambient lighting, such as string lights or pendant lights, to enhance the atmosphere. Add small decorative elements like cushions and throw pillows on the chairs for comfort. Ensure there is a clear pathway for people to move around easily within the seating area.