The generator uses HSL (Hue, Saturation, Lightness) color theory. It derives the complementary color by rotating the hue 180 degrees, analogous colors by rotating ±30 degrees, and monochromatic variants by keeping the hue and saturation constant while shifting the lightness up or down by 20 percent.
A complementary color is the color directly opposite your base color on the color wheel — 180 degrees away in hue. Complementary pairs create maximum contrast and visual pop, making them ideal for call-to-action buttons, highlights, and accent elements in design.
Click "Copy CSS Code" to copy the generated CSS custom property block to your clipboard. Paste it inside the :root selector in your stylesheet. You can then reference each color anywhere in your CSS using var(--base-color), var(--complement-color), and so on.