Darkvision is a sense trait that modifies how a creature sees in areas with little or no light.
In Starfall Galaxy (following PF2e/SF2e style), your vision rules can be summarized as

Normal vision: You need light to see clearly; darkness beyond lit areas is effectively unseen.

Low-Light Vision: You see better in dim light, treating it as normal light, but still cannot see in complete darkness.

Darkvision: You can see in areas of darkness and dim light as though they were normal light, but you don’t perceive color—everything appears in grayscale.

Mechanically, this means:

• You ignore concealment from darkness within your darkvision range.

• You still cannot see through solid obstacles, fog, or other forms of concealment not based on light.

• Stealth, cover, and other visibility rules apply normally; darkvision just removes “it’s dark” as the main obstacle.