js---页面停留时间，

<div> 停留时间：<input type="text"> </div>
      <script>
        let inpu_ = document.querySelector("input")
        function double(mat) {
            return 10 > mat ? "0" + mat : mat;
        }
        let date = 0;
        let hour = 0;
        let minute = 0;
        let second = 0;
        setInterval(function () {
            second++;
            if (second === 60) {
                minute += 1;
                second = 0;
            }
            if (minute === 60) {
                hour += 1;
                minute = 0;
            }
            if (hour === 24) {
                date += 1;
                hour = 0;
            }
            days = double(date) + "天：" + double(hour) + ":" + double(minute) + ":" + double(second);
            inpu_.value = days;
        }, 1000)
    </script>