Building a modal in React with React Portals

React Portals offer a powerful way to render components outside the default DOM hierarchy without altering the parent-child relationship, which is particularly useful for elements such as modals, tooltips, and overlays that need to appear on top of all other content. This technique involves using the `createPortal` function from `react-dom` to append elements to the body, ensuring they have higher precedence in the DOM hierarchy. By using hooks like `useLayoutEffect` for DOM manipulation and `CSSTransition` for smoother UI transitions, developers can efficiently manage dynamic content and visibility without performance drawbacks. The article demonstrates creating a modal with React Portals, addressing challenges like handling dynamic IDs and cleanup, and discusses additional use cases for React Portals, including profile hovercards, full-page loading screens, and dropdowns. The flexibility of React Portals makes them a valuable tool for creating layered user interfaces that require elements to overlay other content seamlessly.