WebGradients is a free collection of 180 linear gradients that you can use as content backdrops in any part of your website.

Beautiful Color Palettes

RGB颜色值与十六进制颜色码转换工具，能将RGB颜色值与十六进制颜色码相互转换

提供渐变色和配色方案，还能从提供的图片中提取主要配色

Beautiful colored gradients

Curated gradients for designers and developers