public/404.html
<!DOCTYPE html>
<html class="dark">
<meta charset="utf-8">
<title>404: Not Found</title>
<link rel="stylesheet" href="/assets/error/style.css">
<body <% if @traceback %>class="error-message"<% end %>>
<h1>404: Requested resource was not found</h1>
<% if @message.present? %>
<div><%= @message %></div>
<% end %>
<% if !@traceback %>
<div class="error-image" style="background-image: url(/assets/error/error-2.svg)"></div>
<p>Sorry, but the Phoenix is not able to find your resource. Try checking the URL for errors.</p>
<% else %>
<div><%= @exception.message %></div>
<% if @exception.backtrace %>
<div>Traceback:</div>
<% @exception.backtrace.each {|row| %>
<%= row %><br>
<% } %>
<% end %>
<% end %>
</body>
</html>