Hide sidebar

Hi there,

CSS is needed:

@media (max-width: 768px) {
    .sidebar, .footer-widgets {
        display: none;
    }
}

Adding CSS: https://docs.generatepress.com/article/adding-css/

Let me know if this helps :)

It works, thanks!

And is there a way to make a custom sidebar for mobile that doesn't show on desktop?

You could try using the built-in hide-on classes to hide one or the other:
https://docs.generatepress.com/article/responsive-display/#using-our-hide-on-classes

How can I also hide the footer widgets on mobile only?

Edited the CSS here:
https://generatepress.com/forums/topic/hide-sidebar/#post-1199930