CSS3 flip card number sample code

<ul></ul>

 body{background: #000;}
     ul{
         list-style: none;
         margin:100px 0;
         display: flex;
         justify-content:center;
         line-height: 56px;
         height:56px;
         font-size: 39.6px;
         color: #FFFFFF;
         transform-style:preserve-3d;
         perspective:1000px;
     }
     li{
        height:56px;
        margin:0 10px;
        background:none;
        width:16px;
        position: relative;
     }
     .num{
        width:46px;
        transform-style:preserve-3d;
        perspective:1000px;
        transform:rotateY(0deg);
        transition: 1s all ease;
    }
    p{
        height:56px;
        width:46px;
        text-align: center;
        background: #EC2C5C;
        border-radius: 2.57px;
        position: absolute;
    }
    
    p:nth-child(2){
        transform: scalex(-1) translateZ(-1px);
    }

<script>
var number=9999993,
    numArr=addComma(number),
    aNum=[],
    oUl=document.getElementsByTagName('ul')[0];
for(let i=0;i<numArr.length;i++){
    let li = document.createElement('li');
    oUl.appendChild(li);
    if(numArr[i]==',')
    li.innerHTML=',';
    else
    li.innerHTML='<p>'+numArr[i]+'</p><p></p>',
    li.className='num',
    li.deg=0,
    aNum.push(li);
};

setInterval(function(){
    let changeNum=number+1+'';
    let changeArr = addComma(changeNum),
        difference=changeArr.length-numArr.length;
    if(difference){
        for(let i=0;i<difference;i++){
            let li = document.createElement('li');
            oUl.insertBefore(li,oUl.children[0]);
            if(changeArr[i]==',')
            li.innerHTML=',';
            else
            li.innerHTML='<p>'+changeArr[i]+'</p><p></p>',
            li.className='num',
            li.deg=0,
            aNum.unshift(li);
        };
    };
    number+='';
    for(let i=changeNum.length-number.length;i<changeNum.length;i++){
        if(changeNum[i]==number[i])continue;
        let deg = aNum[i].deg;
        aNum[i].deg=deg=deg+180;
        let index=(deg/180)%2;
        aNum[i].children[index].innerHTML=changeNum[i];
        aNum[i].style.transform='rotateY('+deg+'deg)';
    };
    number=Number(changeNum);
    numArr=changeArr;
},2000);


function addComma(num){ //Add a bean number for every three digits return (num || 0).toString().replace(/(\d)(?=(?:\d{3})+$)/g, '$1,');
};
</script>