<!doctype html>
<html lang="en">
    <head>
        <meta charset="UTF-8" />
        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
        <title>WebRTC</title>

        <style type="text/css">
            body {
                margin: 0;
                font-size: 20px;
            }

            .centered {
                position: absolute;
                top: 40%;
                left: 50%;
                transform: translate(-50%, -50%);
            }

            .video-