<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>

</body>
<script>
    var ua = navigator.userAgent.toLowerCase();
    alert(ua)
    if (ua.match(/mqqbrowser/i) == "mqqbrowser") {
//            $(".shadow-img").fadeIn(500)
        alert("我真的是QQ")
    }
</script>
</html>