ui-selectableScroll/jquery-ui-ext.css

/* helper css for selectableScroll */
.ui-selectable-helper.no-top {
  border-top: 0;
}
.ui-selectable-helper.no-right {
  border-right: 0;
}
.ui-selectable-helper.no-bottom {
  border-bottom: 0;
}
.ui-selectable-helper.no-left {
  border-left: 0;
}