CSS

CSS stands for Cascading Style Sheets and describes the visual presentation of HTML or XML documents. Rules select elements and assign properties for layout, spacing, colour, typography, animation, or different output media. The cascade determines which declaration applies based on origin, layers, specificity, and order.

Media queries and flexible layout methods such as Flexbox and Grid enable responsive interfaces. Good stylesheets account for maintainability, loading performance, contrast, zoom, user preferences, and different input methods. CSS separates presentation from content, although structure and design still need to be planned and tested together.

• Controls layout, typography, and colour
• Cascade and specificity determine applied rules
• Flexbox, Grid, and media queries for responsive layouts
• Respect contrast and user preferences
• Organise structure and styles for maintainability