How to add a "Dark Mode" to your React website.

Learn how to add a "Dark Mode" to a React website with Styled-Components and React Hooks that help your site remember a visitor's preferences between visits. See the code from this video at: https://codesandbox.io/s/k9w76695m3 More info on Styled Components at: https://www.styled-components.com More info on Styled Theming at: https://github.com/styled-components/styled-theming