Here is the code my friend (add into the Additional CSS or in your style.css child theme):

/* Hide top header – secondary menu on scroll */
 
#top-header {
    overflow: hidden;
    max-height: 50px;
    transition: max-height .3s ease;
}
 
#top-header.et-fixed-header {
    max-height: 0;
}
 
#main-header {
    transition: top .3s ease;
}
 
#main-header.et-fixed-header {
    top: 0 !important;
}
 
.admin-bar #main-header.et-fixed-header {
    top: 32px !important;
}