header{border-bottom:1px solid #222;margin-bottom:1rem}footer{border-top:1px solid #222;margin-top:1rem}body{color:#222;font-family:sans-serif;line-height:1.5;margin:auto;max-width:768px}body,code{font-size:16px}a{color:#00e;text-decoration:none}.container,pre{padding:16px}