It’s called a mesh gradient and there are some generators for it if you want to take an easy route. For example https://meshgradient.com/. Source: 12 months ago

If you want a bit more control and want to set your own colours, you can try meshgradient.com. It's free and the final image is exported as a high-resolution PNG. Source: over 1 year ago

You can download gradients, make them yourself with design software or gradient generators, and then animate them using basic CSS—Partiful uses a 12 second linear animation that basically scrolls a static gradient image. Source: over 1 year ago

Mesh gradient - I use this site to create the CSS needed https://meshgradient.com/. Source: over 1 year ago

If you are like me and struggle with finding an aesthetic cover for your Notion, I recommend you try out Mesh Gradients, the aesthetic is sooo good ;). Source: over 1 year ago

CSSGradient is an online tool that helps users create custom CSS gradient backgrounds. It provides a simple interface that allows users to choose different colors and gradient types, such as linear gradients, radial gradients, repeating gradients, and more. Users can create their favorite gradient effect by dragging and adjusting control points, and can preview the gradient effect in real time. CSSGradient also... - Source: dev.to / about 2 months ago

CssGradient.io - You can find thousands of gradients on this website IN CSS. That's the neat part. (One of my Favorites). Source: 11 months ago

Gradient colors => https://cssgradient.io/gradient-backgrounds/. - Source: dev.to / almost 2 years ago

Thanks! I used this website called CSS Gradients to pick ready made gradient colours, and another one called Coolers for solid colours. Source: about 2 years ago

5.CSSGradient CSS Gradient makes it dead simple to create fresh web gradients. Includes a collection of tools to help you level up your gradient game. - Source: dev.to / over 2 years ago