Set the footer color:

What's happening?

All components show a red border when they re-render. Notice the differences:

• Main with Props: When you click the increment button, only the Main component re-renders. The Footer component is created fresh each time.
• Main with Component: When you click the increment button, both Main and Footer re-render because the footer prop changes on every render.
• Main with useMemo: The Footer component is memoized and only re-renders when the color prop changes, not when the count changes.
• Main with Children: Similar to passing a component, but using the children prop pattern which is more idiomatic in React.