нашел такой код
function getOffsetRect(elem) {
// (1)
var box = elem.getBoundingClientRect()
// (2)
var body = document.body
var docElem = document.documentElement
// (3)
var scrollTop = window.pageYOffset || docElem.scrollTop || body.scrollTop
var scrollLeft = window.pageXOffset || docElem.scrollLeft || body.scrollLeft
// (4)
var clientTop = docElem.clientTop || body.clientTop || 0
var clientLeft = docElem.clientLeft || body.clientLeft || 0
// (5)
var top = box.top + scrollTop - clientTop
var left = box.left + scrollLeft - clientLeft
return { top: Math.round(top), left: Math.round(left) }
}
