Vertical, Arrow
This is a two-way arrow, pointing vertically upward and downward respectively. The arrow is black, gray, red or white, and the thickness of lines adopted by different platforms is different. The size of the arrow and the length of the cross bar connecting the two arrows in the middle are different from platform to platform. The base map of the logo varies from platform to platform. Some platforms depict pure arrows, while others depict a square frame around the arrows, which is blue or gray, but the depth is different. Except for the square presented by Microsoft platform with four right angles and black borders, the squares of other platforms have four sleek corners with certain radians.
The emoji is usually used to express the relationship between up and down, vertical and direct, and can also be extended to express the mutual transformation and two-way traffic.
