Color tolerance is the "hidden grammar of precision" in the narrative of light and shadow—it does not directly determine the coldness, warmth, or brightness of light, yet it governs the "credibility" and "harmony" of colors. In professional fields, it acts as a "color guardian" that preserves the authenticity of art; in commercial spaces, it serves as an "invisible tool" for shaping brand texture; in daily life, it is a "detail code" that affects visual comfort. Understanding color tolerance means understanding "how light accurately conveys the truth of colors"—from technical parameters to sensory experience, ensuring that every beam of light stays on its "predestined color track" and resonates harmoniously with space, objects, and people.