<!DOCTYPE html>
<html>
<head>
<title>Random BG Video</title>
<meta name="viewport" content="width=device-width">
<style>
*{margin:0;
box-sizing:border-box;
}
#video {top:0;
left: 0;
right: 0;
bottom:0;
position:fixed;
min-width:100%;
min-height:100%;
}
</style>
</head>
<body>
<video autoplay muted loop id="video">
<source src="" type="video/mp4" id="vsrc">
Tu navegador no soporta HTML5 Vídeo.
</video>
<script>
var videos=["video1.mp4","video2.mp4","video3.mp4","video4.mp4"];
document.getElementById("video").src=videos[Math.floor(Math.random()*4)+1];</script>
</body>
</html>
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