The design emphasizes the operation panel on the top by contrasting black and white, matte and gloss, like water flowing from the mountains to the valley. The panel also provides a great interface for man-machine interaction. A 15° angle guides the color to the opening section to simplify the function for the most comfortable operating experience. Red signs are attached to each opening section for convenient recognition and use of the product. The reduced molds and parting lines make it more integrated and narrower, as well as easier to install.