10行JS实现文字无缝滚动简单方法

<section class="pro_quota_tip"> 
 <p class="tip_box"> 
 <a href="javascript:;" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >aaaaaaaaa</a> 
 <a href="javascript:;" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >bbbbbbbbbbbbbb</a> 
 <a href="javascript:;" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >ccccccccccc</a> 
 <a href="javascript:;" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >ddddddddddddddd</a> 
 <a href="javascript:;" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" >aaaaaaaaaaaaaa</a> 
 </p> 
</section>

body,#app{
 margin: 0;
 padding: 0;
 font-family:Helvetica;
 background: #f0efef !important;
 width: 100%;
 overflow-x: hidden;
}
a{
 text-decoration: none;
}
.pro_quota_tip{
 background: #fff;
 font-size: 14px;
 overflow: hidden;
 width: 200px;
 height: 49px;
 margin:0 auto;
 margin-top:10%
}
.pro_quota_tip .tip_box{
 position: relative;
}
.pro_quota_tip .tip_box a{
 color: red;
 display: block;
 width: 100%;
 padding:15px 5px;
 white-space:nowrap;
 overflow:hidden;
 text-overflow:ellipsis;
}

var tip_box_a_h = document.querySelectorAll('.tip_box a')[0].offsetHeight;
var i=0;
setInterval(()=>{
 let startScroll = setInterval(()=>{
 i++;
 document.querySelector('.tip_box').style.bottom = (tip_box_a_h/10)*i+'px';
 if(i%10==0)clearInterval(startScroll);
 },50)
 if(i>(10*(document.querySelectorAll('.tip_box a').length-2)))i = 0;
},2500)