Dark mode is an alternative colour scheme with a dark background and light text. Some users have it set at system level and expect the website to adapt. Implementing it is not a simple inversion of colours – pure black with pure white looks unpleasant, so muted shades are used, the saturation of brand colours is adjusted, the intensity of images is reduced, and the text contrast is checked, which must meet the same accessibility requirements as the light version. All interface states need to be tested, including buttons, forms and error messages. For an ordinary presentational website, it is not a necessity; for applications and tools in which people spend long periods, it is now an expected part. If a company implements dark mode, it should maintain it with every design change, otherwise it will fall apart sooner than the light version.
See also: Design System, Website accessibility (WCAG), Typography and readability.
