public/500.html
<!DOCTYPE html>
<html>
<head>
<title>We're sorry, but something went wrong (500)</title>
<style type="text/css">
body { text-align: center; }
</style>
</head>
<body>
<!-- This file lives in public/500.html -->
<img src='/images/500.jpg' alt='500 - Internal Server Error'/>
<br/>
Source: <a href="https://httpcats.herokuapp.com/500">HTTP Status Cats API</a>
</body>
</html>