The scroll-behavior property specifies the scrolling behavior for a scrolling box, when scrolling happens due to navigation or CSSOM scrolling APIs.
Other scrolls, such as those performed by the user, are not affected by this property.
object.style.scrollBehavior = "value";
<'scroll-behavior'> = auto | smooth
The scrolling box is scrolled in an instant fashion.
The scrolling box is scrolled in a smooth fashion using a user-agent-defined timing function over a user-agent-defined period of time.
World Wide Web Consortium (W3C)