Dark Mode is a user interface feature that inverts colors, shifting from a light to a dark palette, to reduce eye strain and improve usability, particularly in low-light environments. Traditionally, implementing Dark Mode for web applications required complex systems involving multiple CSS files for light and dark themes. However, with the introduction of System Wide Dark Mode and the prefers-color-scheme media query, developers can now more easily adapt their applications to user preferences by using CSS Variables to dynamically update styles at runtime. These advancements allow for a streamlined approach to theming, enabling applications to support Dark Mode across browsers that recognize these features while providing fallback options for those that do not. This development, though not yet universally supported, represents a significant step forward in enhancing the user experience by accommodating different viewing preferences.