To make a Burger Icon next to the Navigation Bar on the Desktop, you can use this code to the Custom CSS box

@media screen and (min-width:992px) {
.header-burger {
    display: flex !important;
    margin-left: 2.5vw;
}
.header--menu-open .header-menu {
    opacity: 1 !important;
    visibility: visible !important
}}

And you will have