CSS decides how an HTML document is presented. Start by tracing the cascade, sizing one box, and testing a layout at narrow width and high zoom; then move to the section that matches the failure you need to solve.
Start with the existing lessons
- CSS selectors and the cascade: trace the winning declaration
- CSS box model and layout: size content without accidental overflow
- Responsive CSS: keep reading order and controls usable
CSS learning paths
- CSS Foundations
- CSS Selectors
- CSS Layout
- CSS Type and Media
- Responsive CSS
- CSS Interaction and Accessibility
- CSS Projects
- CSS Quizzes
Build on the document
Common Mistakes
- Do not use CSS to supply the only copy of a status or label.
- Do not judge a layout only at one viewport width or default zoom.
- Do not add specificity until the winning cascade rule is understood.
Applied CSS decisions
- Native CSS nesting: group states without raising specificity by accident
- CSS subgrid: align nested card content to shared tracks
- CSS data tables: preserve headers when columns get narrow
- CSS form states: make errors and disabled fields explicit
- CSS audit table project: responsive records without dropped columns