Background Shrinking

How can I set it to automatically fit the entire screen no matter the size?

For example, this:

body {
    background: url('https://encrypted-tbn1.gstatic.com/images?q=tbn:ANd9GcR3vcDiEe2CndloxajnUj4Qj9CkEdyDgtXV8o0kOTEZ66Bv_ujB') center no-repeat;
    background-size: 100% 100%;
    background-attachment: fixed;
}

You might want to lose background-attachment: fixed;

@digitalninjaza, almost yes, but, you didn’t provide an image URL, you did provide the absolute path to your child theme.

Instead of /public_html/.../listify-child/, paste an image URL which will be used as background ( e.g http://site.ext/wp-content/uploads/2015/07/bg.png )..

By the way the theme you are using is commercial and as per Forum Welcome, commercial products aren’t supported in these forums.

Good point! I use static sprites all the time, directly uploaded in the server.

Let us know how it goes 🙂

OK – assuming you got the image hosted already ( you have got its path, http://blablab.la/img.png .. ), just insert it in the place of /public_html/.../listify-child/ which you showed in the screenshot.

OK. the full path then will be : http://yoursite.ext/wp-content/themes/listify-child/{folder}/{img_name.extension}

If you are putting the CSS in your child theme’s style file, then this path would work too: ./{folder}/{img_name.extension}

Yes, like that, but the issue is, your site’s CSS and JS files aren’t queued in the secure protocol you are using.

You have to either switch back to normal http protocol, or, force plugins and themes to enqueue their scripts in HTTPS, and then you can check the background..

I don’t like Cloudflare’s free flexible SSL a lot, I used for a while, then noticed that in windows XP the site isn’t accessible at all due to some SSL error I forgot its name..

You’ve got a lot of instructions here already

https://wordpress.org/support/topic/urgent-orange-screen