Dark Background UI Design (Dark UI Design) is a term used to refer to a web-based application layout interface that uses mostly dark backgrounds and elements to create a ‘dark’ color scheme. In most cases, dark interfaces can be the only color theme for a given website or application or can be toggled on (in our case) easily through customizable settings.
Technically, a User Experience (UX) Design encompasses all aspects of the end-users interaction with a web business company, its services, and its products. It's important to distinguish the total User Experience from the User Interface (UI), even though the UI is obviously an extremely important part of the design.
In web design, Color Contrast is the difference in light between the font (or anything in the foreground) and its background. So, in terms of web accessibility, how well one color stands out from another color determines whether or not most people will be able to read the information.