Градиенты
https://webgradients.com/
Тут собрана инфомация о цвете
https://webgradients.com/
https://picular.co/
https://meyerweb.com/eric/tools/color-blend/#FF0000:FFFF00:6:hex
https://color.hailpixel.com/
https://www.colorhexa.com/
https://colorhunt.co/
https://meyerweb.com/eric/tools/color-blend/#FF0000:FFFF00:6:hex
https://color.hailpixel.com/
https://www.colorhexa.com/
https://flatuicolors.com