京东快递查询

<div>
  <span style="font-size:24px;"></span>
  <input type="text">
</div>
<script>
  var txt=document.querySelector("[type=text]");
  var span=document.querySelector('span');
  txt.addEventListener('keyup',function () {//按键弹起
    span.innerHTML=txt.value;//
  })
  txt.addEventListener("blur",function () {//失去焦点
      txt.style.color="#ccc";
      span.style.display='none';
  })
  txt.addEventListener("focus",function () {//获得焦点

      txt.style.color="";
      span.style.display='block';
  })
</script>