Adjust gradient for poster background image

Quick answer：

Adjusting the gradient for a poster background image involves changing the color blending between two or more colors to create a smooth transition. This is typically done in graphic design software like Adobe Photoshop or Illustrator. The process includes selecting a gradient tool, choosing the desired colors, and then adjusting the gradient stops to achieve the desired effect. The gradient can be linear or radial, and can be used to add depth, emphasis, or aesthetic appeal to the poster design.