div 自动跟着滚动条移动

<script>
$(function () {
  $(window).scroll(function () {
    var top = $(window).scrollTop() + 20;
    //var left = $(window).scrollLeft() + 320;
    $("#refresh").animate({ "top": top }, 1); 
    //$("#refresh").css({ left: left + "px", top: top + "px" });
  });
});
script>
 
<div style="position:absolute;right:0px;top:20px;width:70px;height:20px;z-index:200;" id="refresh" >
    <button type="button" style="width:70px;" class="btn btn-sm btn-danger" onclick="location.reload();"><span class="glyphicon glyphicon-refresh">span>刷新button>
div>