Why are my blocks not connected to layout (Jade)?

Question

Node.js

Hello,
I can't find the reason why my blocks are not showing up when rendering the page.
Here's how I connect them:
layout:

doctype html
html
  head
    title
    link(rel='stylesheet', href='/stylesheets/style.css')
    link(rel='stylesheet', href='//code.jquery.com/ui/1.11.4/themes/smoothness/jquery-ui.css')
    script(src="https://code.jquery.com/jquery-2.1.4.min.js")
    script(src="//code.jquery.com/ui/1.11.4/jquery-ui.js")
  body
    block header

    block content

    block foot

index.jade:

extends layout

block content
  h1 Hello on Index page

header.jade:

extends layout

block header
   h2 Hello from Header block

app.js

var express = require('express');
var path = require('path');
var favicon = require('serve-favicon');
var logger = require('morgan');
var cookieParser = require('cookie-parser');
var bodyParser = require('body-parser');

var routes = require('./routes/index');
var foot = require('./routes/foot');
var header = require('./routes/header');

var app = express();

// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'jade');

// uncomment after placing your favicon in /public
//app.use(favicon(path.join(__dirname, 'public', 'favicon.ico')));
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));

app.use('/', routes);
app.use('/foot', foot);
app.use('/header', header);

// catch 404 and forward to error handler
app.use(function(req, res, next) {
  var err = new Error('Not Found');
  err.status = 404;
  next(err);
});

// error handlers

// development error handler
// will print stacktrace
if (app.get('env') === 'development') {
  app.use(function(err, req, res, next) {
    res.status(err.status || 500);
    res.render('error', {
      message: err.message,
      error: err
    });
  });
}

// production error handler
// no stacktraces leaked to user
app.use(function(err, req, res, next) {
  res.status(err.status || 500);
  res.render('error', {
    message: err.message,
    error: {}
  });
});


module.exports = app;

index.js

var express = require('express');
var router = express.Router();

/* GET home page. */
router.get('/', function(req, res, next) {
  res.render('index');
});

module.exports = router;

People! How to connect them correctly?
Thanks in advance!

Answer 1

layout:

doctype html
html
  head
    title
    link(rel='stylesheet', href='/stylesheets/style.css')
    link(rel='stylesheet', href='//code.jquery.com/ui/1.11.4/themes/smoothness/jquery-ui.css')
    script(src="https://code.jquery.com/jquery-2.1.4.min.js")
    script(src="//code.jquery.com/ui/1.11.4/jquery-ui.js")
  body
    block header
    block content
    block foot

index.jade:

extends layout
block header
    include header
block content
  h1 Hello on Index page

header.jade:
h2 Hello from Header block