Wells Full-Width Excluding Specific Pages

I've applied the following code to expand my site's max-width to full-width and am trying to exclude one specific page. I found the page's ID code and tried to implement it, but the code failed to exclude the one page: specifically, my About page (https://www.minaroy.com/about). Any ideas what I can do to fix this? 

Custom CSS
/* Apply to all pages */
div#canvasWrapper {
    max-width: 100% !important;
}

/* Exclude specific page */
#page-5423a209e4b0a5427e4538f4 div#canvasWrapper {
    max-width: 1800px !important; /* or any other value you prefer */
}

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