red 3

Red 3 (#CD0000) is a darker, deeply saturated red from the X11 colour system, part of the calibrated red series where higher numbers indicate progressively darker shades derived from the same hue family. The reduced luminosity gives it a more serious, less alarming quality than pure red while maintaining strong emotional associations with urgency, danger, and intensity. It is used in data visualisation, UI design, and technical graphics where a rich but controlled red is needed.

Pure red is the color of adrenaline, passion, and urgency. It raises heart rate and stimulates appetite, which is why fast-food chains and sale banners rely on it worldwide. Culturally, red signifies luck and prosperity in East Asia while representing danger and prohibition in Western road signage.

Medium red is ideal for call-to-action buttons, sale badges, and notification dots where instant attention is needed. It should be used sparingly as an accent rather than a dominant background to avoid visual fatigue. Red pairs effectively with white text for maximum legibility in buttons and banners.