Four gradient colors on the layer

Quick answer：

Gradient colors on a layer refer to a smooth transition of color across an area. In graphic design, this technique is used to create visual depth and a sense of continuity. It involves blending two or more colors in a smooth and seamless manner. Layers in graphic design software, like Photoshop, allow users to apply gradients to specific areas of an image or design, enhancing visual appeal and conveying emotions or themes. Common uses include background fills, text effects, and creating complex patterns.