Posts Feature Image in Header section but full-width

[thedarkmaster 0]

Hi everyone, I'm trying to set the featured image of every post as the header image. But I'd like it to be full-width, covering the whole page. Something that looks like this page: https://mushashugyofans.wordpress.com/2016/01/22/clash-of-heroes-2/

You see that in this wordpress site, there's an header section showing the featured image as large as the whole page. I tried installing a wordpress widget able of displaying a post's featured image, but when I add it to my header section using widgetizer, of course the picture dimension is small and not responsive.

I thought that maybe there's a way for pagelines to set a post featured image as a section background? That would be a workaround, I'd set the section width to page width and I'd be ready to go... any other idea / workaround?