.layout-content.boxed #primary – you have a padding of 25% on all 4 sides…
another is
.container {
padding-right: 15px;
padding-left: 15px;}

Ya’ll want to override these or edit your style sheet.
It all depends on what you’re comfortable with.

Tried this:

.container {
padding-right: 0px;
padding-left: 0px;}

And this:

.layout-content.boxed #primary {
padding-right: 0px;
padding-left: 0px;}

And they both leave – although indeed smaller – some padding.
Is there anything else you would suggest?

@media (min-width: 768px)
style.min.css:2
.layout-content.boxed #primary {
padding: 25px;
}

I really don’t understand why it’s happening, here’s the CSS code I used:
https://snag.gy/5ixKNb.jpg

And for some reason it’s overridden with this:
https://snag.gy/pGSDq5.jpg

When I alter the 25px in the inspector it works, just like it does for you… but why the hell it overrides the CSS I entered?

@media only screen and (min-width: 768px) {
.layout-content.boxed #primary{padding: 0 !important;}
}