gistfile1.js

var page = require('webpage').create();

page.settings.userAgent = 'Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/36.0.1976.2 Safari/537.36';

page.viewportSize = {
    width: 1024,
    height: 768
};

page.onConsoleMessage = function(msg) {
    console.log(msg);
};

page.open('http://www.trivago.co.uk/', function(status) {
    if (status === 'success') {
        page.evaluate(function() {
            $('#js_go').click();

            // wait a bit
            setTimeout(function() {
               $('.item_nav:first > li:first').click()
            }, 5000);
        });
        setTimeout(function() {
            page.render('out.png');
            phantom.exit();
        }, 10000);
    } else {
        console.log('unable to load web page');
    }
});

gistfile2.js

var casper = require('casper').create({
    pageSettings: {
        userAgent: 'Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/36.0.1976.2 Safari/537.36'
    },
    viewportSize: {
        width: 1024,
        height: 768
    },
    waitTimeout: 10000
});

casper.start('http://www.trivago.co.uk', function() {
    this.click('#js_go');
    
    this.wait(5000, function post() {
        this.evaluate(function() {
            $('.item_nav:first > li:first').click();
        });
        this.wait(3000, function() {
            this.capture('casper.png');
            casper.exit();
        });
    });
});

casper.run();