errorPages/400.html
<html>
<head>
<title>Error 400</title>
<meta charset="utf-8">
</head>
<body style="
background-color: #f0f0f0;
color: #ACACAC;
text-shadow: 0 -1px #fff;
font: 20px Source Sans Pro, Helvetica Neue, Arial;
font-weight: 200;
text-align: center;
padding: 10px;
padding-top: 100px;
">
<span style="font-size: 80px;">✘</span><br>
This URL is not allowed.
</body>
</html>