/**
 * The overlay's one static stylesheet, injected into the shadow root.
 *
 * Scope discipline: **every rule targets a `.cds-*` class or an explicit
 * `#id::pseudo-element`.** A bare `button { … }` here would silently restyle every
 * inline-styled control in the overlay, since the shadow root is our whole world.
 *
 * Division of labour with the rest of the overlay: geometry (`top`/`left`/`width`)
 * stays in JS, because it depends on the panel-position preference and the compact
 * breakpoint — runtime state a media query cannot read, and inline values a
 * stylesheet cannot override without `!important`. What lives here is everything a
 * media query *can* own: pointer ergonomics, `touch-action`, scroll behaviour, and
 * the slider pseudo-elements that inline styles can never reach.
 */
/** Inject the base sheet once. Called from `getDebugRoot()`. */
export declare function injectBaseStyles(root: ShadowRoot): void;