WordPress 2014 Full Bleed

I am running wordpress on my test server to develop a site for one of my clients, I was wondering how I could take the blog template for the ‘Twenty Fourteen Theme’ for the single pages and the main blog post page to make every image inserted in the blog post and make them into full bleed images (occupying the width of the page). I have already gotten rid of the sidebar and turned the theme into a full page template. I just need to know how to make the post image and featured image pop and maintain responsiveness. Like so: https://medium.com/tech-blogging/3bbbb45587d6