接口 PropertyIndexedKeyframes

interface PropertyIndexedKeyframes {
    composite?: CompositeOperationOrAuto | CompositeOperationOrAuto[];
    easing?: string | string[];
    offset?: number | (null | number)[];
    [property: string]:
        | string
        | string[]
        | number
        | null
        | (number | null)[]
        | undefined;
}