Hi there,
So basically you want that page to have different container width than the rest of the website?
If yes then you can either add this CSS to the Simple CSS metabox of that page:
.generate-sections-container .grid-container.grid-parent {
max-width: 700px;
}
Or find the page ID then use this CSS in the global CSS editor:
.page-id-xx .generate-sections-container .generate-sections-container .grid-container.grid-parent {
max-width: 700px;
}
Adding CSS: https://docs.generatepress.com/article/adding-css/
Let me know.