Adding dark mode to your React app

A practical guide to implementing dark mode in a React app using Emotion themes, React Context, and Hooks. The approach covers defining light and dark theme objects, building a ThemeProvider component with a custom useEffectDarkMode hook that reads from localStorage on mount, and exposing a toggle function via a useTheme hook. The result is a non-intrusive dark mode toggle that persists user preference across sessions without requiring major architectural changes.