手機驗證碼60s等待

html:

<div class="input">
    <input class="tel input_all" type="text" name="tel" placeholder="手機號">
</div>
<div class="input huoqu">
    <input class="yzm input_all" type="text" name="code" placeholder="驗證碼">
    <button class="btn1">獲取驗證碼</button>
</div>
<span class="error"></span>

JavaScript:

var btn1 = document.querySelector('.btn1');
var tel = document.querySelector('.tel');
var error = document.querySelector('.error');
var time = 60;
btn1.onclick = function(){
    var name = tel.value;    
    if (name == "") {
        error.innerHTML='手機號不能爲空!';
        return;
    } 
    else {
        if (!(/^1[3|4|5|7|8]\d{9}$/.test(name))) {
            error.innerHTML='手機號格式有誤.';
             return;
        }
    }
    var timer = setInterval(function(){        
        time--;
        btn1.innerHTML = time + "秒";
        btn1.disabled = true;
        if (time==0) {
            time = 60;
            clearInterval(timer); 
            btn1.innerHTML = "獲取驗證碼";
            btn1.disabled = false;
        }
    },1000);
}