function promptBox(data){
                var promptBox = document.getElementById('promptBox');
                if (data.status == "200"){
                    promptBox.style.display = 'block';
                    promptBox.innerHTML = "推荐成功！";
                    **promptBox.fadeOut(2000);  //这里报错**
                }else{
                    promptBox.style.display = 'block';
                    promptBox.innerHTML = "推荐成功不能再次推荐，请重新选择！！";
                }
            }

报错信息：Uncaught TypeError: promptBox.fadeOut is not a function