Switch

A native checkbox exposed as an immediate on or off setting. CSS only

<label class="ui-choice" for="dark-mode">
  <input class="ui-switch" id="dark-mode" name="dark-mode" type="checkbox" role="switch" checked aria-describedby="dark-mode-description">
  <span data-ui-part="body">
    <span data-ui-part="title">Dark mode</span>
    <span id="dark-mode-description" data-ui-part="description">Follow the documentation theme.</span>
  </span>
</label>

Install

import '@timelessui/components/css/tokens.css'
import '@timelessui/components/css/core/forms.css'
import '@timelessui/components/css/themes/atmosphere/tokens.css'
import '@timelessui/components/css/themes/atmosphere/forms.css'

Anatomy

Parts are authored in your own markup and identified by the selector below, so your CSS can target the same anatomy without loading Timeless styles. Required parts must be present for the component to work. Private data-ui-internal-* hooks are written by the runtime and must never be authored.

ui-choice

Part	Required	Selector	Purpose
`body`	No	`[data-ui-part~='body']`	Wrapper for the title and description beside the control.
`title`	No	`[data-ui-part~='title']`	The choice label text.
`description`	No	`[data-ui-part~='description']`	Supporting copy under the choice label.

Attributes

Every value below is implemented by the stylesheets this component ships. Boolean attributes are presence-based: author the attribute with no value, or omit it.

ui-choice

Attribute	Values	Default	Description
`data-ui-density`	`compact` · `normal` · `spacious`	`normal`	Gap between the control and its label.

State

Native attributes, ARIA, and platform pseudo-classes are authoritative. Style state through the selectors below rather than adding your own state classes.

State	Source	How to express it
`invalid`	native	Native `:invalid`, or `aria-invalid="true"`.
`disabled`	native	Native `disabled`.

Styling

Root identity: ui-switch, ui-choice. Required stylesheets: tokens.css, core/forms.css, themes/atmosphere/tokens.css, themes/atmosphere/forms.css.

This component adds no custom properties of its own. Restyle it through the design tokens or your own CSS.

Design tokens this component reads (26)

These are global Atmosphere tokens. Change them once at the theme level rather than per component.

--ui-accent · --ui-bg-control · --ui-bg-control-muted · --ui-bg-surface · --ui-bg-surface-subtle · --ui-danger · --ui-danger-soft · --ui-disabled-opacity · --ui-duration-fast · --ui-ease-standard · --ui-fg · --ui-fg-muted · --ui-fg-subtle · --ui-focus · --ui-line · --ui-line-strong · --ui-radius-md · --ui-radius-pill · --ui-radius-sm · --ui-shadow-control · --ui-shadow-inset · --ui-space-1 · --ui-space-2 · --ui-space-3 · --ui-space-4 · --ui-space-5

Accessibility

Keep the native elements, roles, and relationships shown in the example. Timeless adds only the state and keyboard coordination the platform does not already provide, and it never supplies your accessible names — those depend on your content.

Follows the Switch pattern from the ARIA Authoring Practices Guide.

A native input[type="checkbox"] with role="switch", which is the whole component: Tab reaches it, Space toggles it, the checked state is :checked, and it submits and resets with the form. role="switch" changes only how it is announced — on or off rather than checked or unchecked — so use it when the control takes effect immediately and leave it off when the change needs saving. Label it as you would any checkbox, and do not add aria-checked; the native state is authoritative and the two can disagree.

Before JavaScript runs

This primitive is CSS only. There is nothing to register and nothing to wait for.

More examples

Open Switch in StoryLite for variants, controls, and manual testing.