export interface ShadyCSSMixin {
    render(): string;
}
/**
 * ShadyCSSMixins applies ShadyCSS to the template if it's available
 * in global window to support unsupported browsers.
 *
 * @mixin
 * @example
 * class MyClass extends ShadyCSSMixin implements ShadyCSSMixin {
 *     static get is() {
 *         return 'my-class'
 *     }
 *
 *     render() {
 *         return `
 *             <style>:host { color: blue} </style>
 *             <slot></slot>
 *         `;
 *     }
 * }
 */
export declare const ShadyCSSMixin: (Base?: any) => any;