/**
 * Mixes two colors together by calculating the average of each of the RGB components.
 *
 * By default the weight is 0.5 meaning that half of the first color and half the second
 * color should be used. Optionally the weight can be modified by providing a number
 * as the first argument. 0.25 means that a quarter of the first color and three quarters
 * of the second color should be used.
 *
 * @example
 * background: mix(0.5, '#f00', '#00f')
 * background: mix(0.25, '#f00', '#00f')
 * background: mix(0.5, 'rgba(255, 0, 0, 0.5)', '#00f')
 */
export declare function mix(weight: number | undefined, color: string, otherColor: string): string;