Overflow
Overflow is what happens when content is larger than its box. CSS can show it, clip it, or let people scroll it.
Another example
A code sample scrolls sideways while the article keeps its normal vertical flow.
Main parts
- 01Outer constraint
- 02Content and spacing model
- 03Computed size or reflow result
Use it when
Set overflow on purpose whenever content may grow beyond a limited area.
Do not use it when
Never use overflow hidden if it cuts off focus rings, menus, or actions.
Name used in code
overflow Before you ship
Check content order, shared design values, component consistency, contrast, zoom, and layout changes by screen size. Verify every theme, language, and state. If there is motion, offer an equal reduced-motion experience.
Outcome: Use or define Overflow to make the visual experience clear and easy to use. User context: A code sample scrolls sideways while the article keeps its normal vertical flow. Design concept to apply: Overflow. Why it fits: Set overflow on purpose whenever content may grow beyond a limited area. Do not use it when: Never use overflow hidden if it cuts off focus rings, menus, or actions. Design requirements: Set the content order, shared design values, and reusable components. Define how the layout changes by screen size and state. Keep useful design choices separate from decoration. Inclusion and resilience: Check contrast, zoom, languages, themes, and reduced motion when needed. Do not use color or effects as the only way to show meaning. Acceptance criteria: The design stays clear on phones and desktops, at zoom, in every theme, and in all supported languages. Interactive states stay clear and consistent. Evidence and limits (evidence boundary): A formal document may still be a draft, release candidate, or final version. Check its status and browser or platform support. Unknowns to confirm: Brand limits, amount of content, supported themes and languages, target devices, and design-system rules.
Check this request
Review the current use of Overflow. Definition: Overflow is what happens when content is larger than its box. CSS can show it, clip it, or let people scroll it. Release checks: Check content order, shared design values, component consistency, contrast, zoom, and layout changes by screen size. Verify every theme, language, and state. If there is motion, offer an equal reduced-motion experience. Before changing code, report the evidence you found, gaps, severity, and the smallest safe fix.