message: check wrapper position
diff: @@ -448,6 +448,7 @@ export function initMixin(BScroll) {
  }
  BScroll.prototype.refresh = function () {
  + const isWrapperStatic = window.getComputedStyle(this.wrapper, null).position === 'static'
  let wrapperRect = getRect(this.wrapper)
  this.wrapperWidth = wrapperRect.width
  this.wrapperHeight = wrapperRect.height
  @@ -459,6 +460,11 @@ export function initMixin(BScroll) {
  this.relativeX = scrollerRect.left
  this.relativeY = scrollerRect.top
  + if (isWrapperStatic) {
  + this.relativeX -= wrapperRect.left
  + this.relativeY -= wrapperRect.top
  + }
  +
  this.minScrollX = 0
  this.minScrollY = 0
  