<!DOCTYPE html>
<html lang="en">
<head>
<style>
html {overflow:hidden; }
body {background-color:#000; color:#fff; height:100%; width:100%; overflow:hidden; position:absolute; margin:0; padding:0; } 
video, audio {width:100%; height:100%; }
.message { text-align:center; margin:10px; font-size:19px; line-height:34px; }
</style>
</head>
<body>
    __body__
    <bx_if:message>
        <div class="message">__message__</div>
    </bx_if:message>    
</body>
</html>
