Skeleton Screen

A design system is a collection of reusable components, guidelines, and standards that ensure visual and functional consistency across a product or suite of products. It typically includes a component library, design tokens, typography rules, color palettes, and documentation. Design systems bridge the gap between designers and developers, enabling teams to build interfaces faster while maintaining a unified look and feel.

Flexbox (Flexible Box Layout) is a one-dimensional CSS layout model designed for distributing space and aligning items within a container along a single axis — either horizontal or vertical. It excels at handling dynamic content sizes, centering elements, and creating flexible navigation bars, card rows, and form layouts. Properties like `justify-content`, `align-items`, and `flex-grow` give you fine-grained control over how items share available space.

Accessibility (often abbreviated a11y) is the practice of designing and building websites and apps so they can be used by everyone, including people with visual, motor, auditory, or cognitive disabilities. This involves proper semantic markup, keyboard navigation support, sufficient color contrast, and screen reader compatibility. Beyond being an ethical responsibility, accessibility is increasingly a legal requirement in many jurisdictions.

BEM (Block Element Modifier) is a CSS naming convention that structures class names as `.block__element--modifier` to create clear, predictable relationships between HTML and CSS. For example, `.card__title--highlighted` identifies a highlighted title element within a card block. While modern tooling like CSS Modules and utility frameworks have reduced BEM's necessity, it remains widely used in large codebases and design systems where explicit naming conventions aid team coordination.

Drag and drop is an interaction pattern that lets users move, reorder, or transfer UI elements by clicking (or touching), holding, and dragging them to a new position. It's used for file uploads, kanban boards, sortable lists, and layout builders. The HTML Drag and Drop API provides native browser support, while libraries like dnd-kit and react-beautiful-dnd offer more polished, accessible, and touch-friendly implementations.

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.