import { LitElement, type PropertyValues } from "lit";
export type SkySheetBackground = "primary" | "secondary" | "tertiary" | "solid" | "transparent";
export type SkySheetBlurLevel = "none" | "sm" | "md" | "lg";
export type SkySheetShadow = "none" | "sm" | "md" | "lg" | "inset";
export type SkySheetBorder = "none" | "sm" | "md" | "lg";
/** Preset tokens or any CSS length (e.g. `1rem`, `16px`). */
export type SkySheetRadius = string;
/** Preset map includes `xl`; arbitrary values pass through like `resolveRadius`. */
export declare function resolveSheetRadius(input: string): string;
/**
 * @element sky-sheet
 *
 * @summary Themed surface container with configurable background, blur, border, and shadow.
 *
 * @status stable
 * @since 1.0.0
 *
 * @documentation https://sky-ui.com/components/sheet
 *
 * @slot - Content placed inside the sheet container.
 *
 * @property {SkySheetBackground} bg - Background style.
 * @property {SkySheetBlurLevel} blurLevel - Backdrop blur intensity.
 * @property {SkySheetShadow} shadow - Shadow style preset.
 * @property {SkySheetBorder} border - Border style preset.
 * @property {SkySheetRadius} radius - Preset (`none`, `sm`, `md`, `lg`, `xl`) or CSS length (`1rem`, `16px`).
 * @property {string} preset - Named prop preset from nearest `sky-config-provider`. Default: `""`.
 *
 * @Behavior
 * - Applies visual styles directly on `:host` for compact composition.
 * - Uses theme CSS variables for consistent glass and elevation tokens.
 * - Renders slot content without additional wrappers.
 *
 * @example
 * ```html
 * <sky-sheet bg="solid" blur-level="md" shadow="lg" border="md" radius="lg">
 *   <h3>Deployment Summary</h3>
 *   <p>All regional checks passed. Ready to promote to production.</p>
 * </sky-sheet>
 * ```
 * ```vue
 * <template>
 *   <sky-sheet bg="solid" blur-level="md" shadow="lg" border="md" radius="lg">
 *     <h3>Deployment Summary</h3>
 *     <p>All regional checks passed. Ready to promote to production.</p>
 *   </sky-sheet>
 * </template>
 * ```
 * ```jsx
 * export default function Demo() {
 *   return (
 *     <sky-sheet bg="solid" blur-level="md" shadow="lg" border="md" radius="lg">
 *       <h3>Deployment Summary</h3>
 *       <p>All regional checks passed. Ready to promote to production.</p>
 *     </sky-sheet>
 *   );
 * }
 * ```
 */
export declare class SkySheet extends LitElement {
    bg: SkySheetBackground;
    blurLevel: SkySheetBlurLevel;
    shadow: SkySheetShadow;
    border: SkySheetBorder;
    radius: SkySheetRadius;
    connectedCallback(): void;
    private _applyRadiusVar;
    /** After PresetController hostUpdate — paint with current radius. */
    protected update(changed: PropertyValues): void;
    /** Named prop preset from nearest `sky-config-provider`. */
    preset: string;
    private _presets;
    static styles: import("lit").CSSResult;
    render(): import("lit-html").TemplateResult<1>;
}