Responsive Design

Storybook is an open-source tool for building and testing UI components in isolation, outside of your main application. Developers define "stories" — different states and variations of a component — which are rendered in a dedicated browser-based workshop. It supports React, Vue, Angular, and other frameworks, making it invaluable for component documentation, visual regression testing, and collaboration between designers and developers.

Shadow DOM is a browser API that allows you to attach a hidden, encapsulated DOM tree to an element, isolating its styles and markup from the rest of the page. This means CSS defined inside a Shadow DOM won't leak out, and external styles won't bleed in. It's the core technology behind Web Components and is used by frameworks to achieve true style encapsulation without CSS naming conventions or tooling.

Hydration is the process where a client-side JavaScript framework attaches event listeners and interactivity to server-rendered HTML markup. After the server sends pre-rendered HTML for fast initial display, the framework "hydrates" it by reconciling its virtual representation with the existing DOM and making it interactive. Hydration can be expensive on complex pages, which has led to innovations like partial hydration, progressive hydration, and React's selective hydration with Suspense.

Headless UI refers to component libraries that provide behavior, state management, and accessibility logic without any predefined styling or markup. Libraries like Radix Primitives, Headless UI by Tailwind Labs, and React Aria give developers full control over visual presentation while handling complex patterns like focus management, keyboard navigation, and ARIA attributes. This approach decouples functionality from design, making it ideal for custom design systems.

CSS Custom Properties (also called CSS Variables) let you define reusable values with `--my-variable` syntax and reference them anywhere using `var(--my-variable)`. Unlike preprocessor variables in Sass or Less, they are live in the browser, cascade through the DOM, and can be updated dynamically with JavaScript. They're essential for theming systems, dark mode implementations, and maintaining consistent design tokens across large stylesheets.

Static Site Generation (SSG) is a rendering strategy where HTML pages are pre-built at build time rather than generated on each request. The resulting static files can be served from a CDN with extremely fast load times and minimal server infrastructure. Frameworks like Next.js, Gatsby, and Astro support SSG, often combined with Incremental Static Regeneration (ISR) to update specific pages in the background without rebuilding the entire site.