* this function is the object of style properties that will be animated,
* and to what end. Each key within the object represents a style property
* that will also be animated (for example: "height", "top", or "opacity").
*
* this function is the object of style properties that will be animated,
* and to what end. Each key within the object represents a style property
* that will also be animated (for example: "height", "top", or "opacity").
*