CSS
Cascading Style Sheets, is a fundamental web development language used to style and format HTML or XML documents. It enables the separation of content from presentation, allowing developers to control the appearance of web pages. CSS utilizes selectors to target HTML elements and applies properties such as color, font, spacing, and layout. Key concepts include the box model, which defines how elements are rendered, and layout models like Flexbox and Grid for responsive design. CSS enables transitions and animations, enhancing user experience, while media queries facilitate design adjustments based on device characteristics. Understanding CSS is essential for crafting visually appealing, responsive, and well-organized web pages.