Untitled

<html>

<head>
    <title>Реклама гаража</title>
</head>

<body style='background-color:#131313;'>
    <div id='wrapper' style='position:relative;height:100%;width:100%;'>
        <div id='adv-block' style='background:#fff;height:50%;width:50%;display:none; margin: auto; position: absolute; top: 0; left: 0; bottom: 0; right: 0;border-radius: 10px;overflow: hidden;'>
            <div style='text-align: center;color:#1a1a1a;'>
                <h1>Продам гараж</h1>
                <div>
                    Рекламу можно закрыть через <span id="timer-counter">10</span>... секунд
                </div>
            </div>
            <div id='button' onclick='closeAdv()' style='position:absolute;right:0;display:none; cursor:pointer; background:#0D91FF;top:0;padding: 15px;'>
                X
            </div>
        </div>
    </div>
    <script>
    window.setTimeout(function() {
        document.getElementById("adv-block").style.display = "block";
    }, 1000);

    function closeAdv() {
        document.getElementById('adv-block').style.display = "none";
    }

    function timer() {
        var obj = document.getElementById('timer-counter');
        obj.innerHTML--;

        if (obj.innerHTML == 0) {
            document.getElementById("button").style.display = "block";
            setTimeout(function() {}, 1000);
        } else {
            setTimeout(timer, 1000);
        }
    }
    setTimeout(timer, 1000);
    </script>
</body>

</html>