题解 | #倒计时#

function second(second) {
    let day=Math.floor(second/(60*60*24)),
        hour=Math.floor((second%(60*60*24))/(60*60)),
        min=Math.floor(second%(60*60)/60),
        s=second%60;
    return {
        day,
        hour,
        min,
        second:s,
    }
}
function render(data) {
   let fullNum=val=>val.toString().length>1?val:`0${val}`;
   let node=document.getElementById('jsCountdown');

    data.day===0?node.children[0].classList.add('hide'):node.children[0].innerHTML=`${fullNum(data.day)}天`;
    node.children[1].innerHTML=`${fullNum(data.hour)}:`;
    node.children[2].innerHTML=`${fullNum(data.min)}:`;
    node.children[3].innerHTML=fullNum(data.second);
}