倒计时
var btn = document.getElementById('btn');
var btn1 = document.getElementById('btn1');
btn.onclick = function() {btn1.style.display = 'block';
btn.style.display = 'none';var fun = setInterval(function() {
var date1 = new Date('2018/07/06 18:00:00')；
;var date2 = new Date();
var old = date1.getTime();
var now = date2.getTime();
var time = old - now;
var moth = Math.floor(time / (1000 * 60 * 60 * 24));var moth2 = time % (1000 * 60 * 60 * 24);
var hour = Math.floor(moth2 / (1000 * 60 * 60));
var hour2 = time % (1000 * 60 * 60);
var min = Math.floor(hour2 / (1000 * 60));
var min2 = time % (1000 * 60);
var sec = Math.floor(min2 / (1000));
document.getElementById('dome1').innerHTML = '距离暑假还有' + '
';
document.getElementById('dome').innerHTML = +moth + '日' + hour + '时' + min + '分' + sec + '秒';
})
btn1.onclick = function() {btn1.style.display = 'none';btn.style.display = 'block';
clearInterval(fun);
alert('您点击了停止定时，定时定在了' + dome.innerHTML
)}
}
