Set index page node js

How do you index.php or index.html using node, so when you go to blahblah.com your node site loads up.

If have the app.js right, now the browser just needs to know where to find the index file

/*
* Module dependencies
*/
var express = require('express')
, stylus = require('stylus')
, nib = require('nib')

var logger = require('morgan')
var app = express()
function compile(str, path) {
return stylus(str)
.set('filename', path)
.use(nib())
}
app.set('views', __dirname + '/views')
app.set('view engine', 'jade')
app.use(logger('dev'));
app.use(stylus.middleware(
 { src: __dirname + '/public'
, compile: compile
}
))
app.use(express.static(__dirname + '/public'))

app.get('/', function (req, res) {
res.render('index',{title : 'CheckMe',subheader:'health and fitness for        kids',logo:'<img src="images/logo.png" alt="">'})
})
app.listen(3000)