Express JS beginner. index.jade does not appear in layout.jade

I have the layout.jade with this code:

doctype html
block head
title= title
link(rel='stylesheet', href='/stylesheets/style.css')
body
header#banner
h1 Awesome Chat
block content
footer Hope you enjoy your stay here

In my index.jade I extend the layout.jade:

extends layout
block content
section#chatroom
div#messages
input#message(type='text', placeholder='Enter your message here')
input#send(type='button', value='Send')

why this does not appear on my page? what is the error? thank you!

via Andrew T