# Layout containment

contain: layout: nothing inside affects layout outside.

## What is **layout containment**?

**Layout containment** (`contain: layout`) promises that nothing inside an element affects layout outside it, so the browser can skip work.

```css
.chat-widget { contain: layout; }
```

Level: Master · [More CSS terms at this level](https://www.ask-codey.com/glossary/subjects/css/master)

Updated: September 27, 2026

Source: https://www.ask-codey.com/glossary/layout-containment