Hi there,
Try increasing the menu item height with the mobile toggle:
https://docs.generatepress.com/article/menu-item-height-width/
There is also 10px padding added by default which you can remove with this CSS:
.mobile-header-navigation .mobile-header-logo img {
padding: 0;
}
Adding CSS: https://docs.generatepress.com/article/adding-css/
That being said, the mobile header logo is supposed to be something small. It would work better if only use the icon without the site title.
Let me know if this helps 🙂