I have been trying to figure this out. I made some progress, but did not find a solution yet. Just sharing where I am so far.
The code below DOES set the page width when I adjust the max-width to a percentage, but it includes all pages (home, posts, etc.).
I want to leave the home page at full width, and be sure any changes I make do not affect mobile devices.
[stylesheet code lines 645-650]
margin: 0 auto;
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