JavaScript实现短信发送按钮倒计时功能

<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>发送短信</title>
    <style>
        .box {
            width: 360px;
            margin: 100px auto;
        }
    </style>
</head>

<body>
    <div class="box">
        手机号码：<input type="number">
        <button>发送短信</button>
    </div>

    <script>
        var btn = document.querySelector('button');
        var time = 10;
        btn.addEventListener('click', function() {
            btn.disabled = true;
            var timer = setInterval(function() {
                if (time == 0) {
                    // 清除定时器和复原按钮
                    clearInterval(timer);
                    btn.disabled = false;
                    btn.innerHTML = '发送短信';
                    time = 10;
                } else {
                    btn.innerHTML = '剩余' + time + '秒';
                    time--;
                }
            }, 1000);
        });
    </script>
</body>

</html>