Hello,
You would better switch to the mobile menu on this type of width as reducing the font size would be the menu not readable.
Please add this code to the Theme Settings > Custom CSS > Global:
@media (max-width: 1400px){
body .main-header .main-nav{
display:none;
}
body .header-full-width .main-header>.container {
padding-top: 10px;
padding-bottom: 10px;
}
body .sticky-header {
padding-top: 5px;
padding-bottom: 5px;
}
body .right-column .mobile-nav-icon {
display: inline-block;
}
body, html {
max-width: 100%;
}
.document-ready .mobile-nav {
display: inline-block;}
body .sticky-header .main-nav {
display:none;
}
body .site-logo {
width: 50%;
}
body .right-column {
width: 50%;
}
}
Best Regards