Add a transition to 'top' css property to .jspDrag
.jspDrag{
transition: top 0.3s ease-out;
}
It works only for scrollbar, for content you can do the same with .jspPane but it's buggy with mouseWheel
so I suggest to use another library supporting smooth scroll :
- Nice scroll : http://areaaperta.com/nicescroll/demo.html
- Custom content scroller : http://manos.malihu.gr/jquery-custom-content-scroller/