<!DOCTYPE html>
<html lang="en">
    <head>
        <title></title>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1">
        <link href="css/style.css" rel="stylesheet">
        <style type="text/css">
            body { 
                background-color:darkgrey;
                font-family:Arial;
            }

            .demo {
                position:absolute;
                border: 2px solid black;
                box-sizing: border-box;
  