Do you know color-scheme?
It will certainly look familiar, as prefers-color-scheme has been around for longer and is clearly related.
Colour
uchū — the color palette for internet lovers
uchū is the color palette for internet lovers, by NetOperator Wibby.
147 Colors Grid - CSS Color Names
This is a tool to help web designers and developers learn the 147 CSS color names that are available today. The 147 Colors consist of 17 standard plus 130 more.
Cool Backgrounds
Explore a beautifully curated selection of cool backgrounds that you can add to blogs, websites, or as desktop and phone wallpapers.
Colors & Fonts - Home
Discover Colors & Fonts, a platform offering a wide range of color and typography tools for web developers and digital designers.
Scale — color scale generator
Color scale generator by Hayk An
Colors - A nicer color palette for the web by @mrmrs_
Accessible color combinations for prototyping on the web https://clrs.cc/a11y/ via
The good colors
Generate perceptually uniform color palettes with OKLCH, ensuring consistent lightness and chroma. Supports wide gamut displays, checks contrast ratios using APAC, and is optimized for color blindness.
How to pick the least wrong colors
An algorithm for creating color palettes for data visualization
Graduum | Free Mesh Gradients by Niklaus Gerber
A collection of one hundred free high-quality mesh gradients suitable for desktop and mobile use.
Pal
Pal lets you apply an eight-color terminal color palette to any image you upload. Use the keyboard controls to choose a theme, set thresholds, and cycle hues.
Image Hues - Vaisakh Pradeep
Natural, fresh color palettes from random beautiful images