What are the hidden maintenance costs of supporting a dark theme?

The hidden maintenance costs of supporting a dark theme lie in the duplication of design and development efforts. Every new component, page, or feature must be designed, coded, and tested in both light and dark states. This effectively doubles the size of your design system token library and increases the complexity of your QA processes. Content creators must also ensure that all uploaded images, such as transparent PNGs, look correct on both light and dark backgrounds. If your brand uses custom illustrations, these may need to be redrawn or adjusted for the dark theme to prevent visual issues. Over time, these tasks slow down your development velocity and increase the overall cost of website ownership. Without a dedicated team to manage these updates, the dark theme can quickly become outdated and inconsistent. Therefore, you must budget for these ongoing operational costs before launching a dark theme.