Make desktop folder nav stay open, like on mobile, and add an 'x' to escape folder nav

Site URL: https://caper-badger-3s6d.squarespace.com/about

Password: home 

I wish to make desktop folder nav stay open, like on mobile. and add an 'x' to escape folder nav.

Can anyone help? 

Q1. Add to Design > Custom CSS

/* make desktop dropdown always visible */
.header-nav-folder-content {
    opacity: 1 !important;
}

Q2. Add X, complex, overloaded, I can't check it right now :(

10 hours ago, tuanphan said:

Q1. Add to Design > Custom CSS

/* make desktop dropdown always visible */
.header-nav-folder-content {
    opacity: 1 !important;
}

Q2. Add X, complex, overloaded, I can't check it right now 😞

@tuanphan Thank you for replying!