> Fetch clean Markdown by appending `.md` to any page URL under https://signalwire.com/docs or requesting it with the HTTP header `Accept: text/markdown`. The root index at https://signalwire.com/docs/llms.txt lists the available documentation indexes. # sw-ui-responsive-container Aspect-ratio-aware sizing wrapper used to host call surfaces inside `` so the experience adapts gracefully from ultra-wide monitors down to phones. ```html ``` Applies a tiered set of CSS rules based on viewport size: * **≥ 1280 px** (large monitors): 80 vw, 16:9 aspect, height capped at `(width × 9 / 16) + 300 px` to leave room for controls. * **600 px – 1279 px** (laptops, small monitors): 90 vw, same 16:9 baseline. * **≤ 600 px** (mobile portrait): 100 vw minus a 20 px gutter, fluid height up to 85 svh — drops the strict aspect ratio so portrait content fills the screen. * **≤ 500 px tall, ≥ 600 px wide** (landscape phones, short windows): 90 vw, 90 vh max, aspect ratio relaxed. *Class: `SwUiResponsiveContainer` · Module: `packages/web-components/src/components/UI/layout/sw-ui-responsive-container.ts`* ## class: `SwUiResponsiveContainer`, `sw-ui-responsive-container` ### Slots | Name | Description | | ---- | -------------------------------------------------------------- | | | Default slot for the content the container should size around. | ---