Gradient pure blue background poster horizontal

Quick answer：

A gradient pure blue background poster refers to a visual design element commonly used in graphic design, where the color changes from a light blue to a darker blue across the poster. This type of background is often used to convey a sense of calmness, depth, or to highlight other design elements on the poster. Horizontal posters are designed to be wider than they are tall, commonly used for wide formats like billboards or banners.