Display width of site only 900px instead of 1400

Hi,

i have two sites

and

I spawned one from the other.
However at some stage i managed to get the latter site to be almost full width of the screen but cant work out how i did this.

If I “inspect” the pages and view the css, I notice that the main differences are
(on catsystems.is-very-good.org)
.container {
max-width: 1500px;
}

whereas it is
( on catsat.is-very-good.org)
.container {
max-width: 1010px;
}
This ties in with the 1400px and 910px width of the pages.

Can anyone guess what I may have done to get 1400px?
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