Dark mode is not just "invert the colors." A palette that looks great on a white background can look harsh, washed out, or illegible on a dark background. But maintaining two completely separate color systems is expensive and error-prone.
What Changes in Dark Mode
In dark mode, your light bases and dark bases essentially swap roles. Your dark base becomes the background; your light base becomes the text. But your chromatic colors also need adjustment. A saturated blue that looks rich on white can feel overwhelming on near-black.
The Desaturation Principle
The key insight is that chromatic colors generally need lower saturation in dark mode. On a light background, high saturation feels energetic. On a dark background, it feels electric and straining. Reducing saturation by 10 to 20% and increasing lightness by 5 to 10% typically produces a comfortable dark-mode variant.
Building a Dual-Mode Palette
Start with your light-mode palette in PaletteRx. Then ask: for each Primary and Supporting color, does the color maintain contrast against both my light base and my dark base? Check Step 3 to see if colors have passing pairs in both directions.
Mid-range colors (50 to 65% lightness, moderate saturation) tend to be the most versatile. They work on both light and dark backgrounds because they have enough luminance difference from both extremes.
The best dark-mode palettes do not feel like "dark mode." They feel like the same brand in a different light.