@media screen and (max-width: 992px) {
    #mega-menu-wrap-header-menu .mega-menu-toggle.mega-menu-open+#mega-menu-header-menu {
        /* From https://css.glass */
        background: rgba(0, 0, 0, 0.57) !important;
        border-radius: 16px !important;
        box-shadow: 0 4px 30px rgba(0, 0, 0, 0.1) !important;
        backdrop-filter: blur(7.4px) !important;
        -webkit-backdrop-filter: blur(7.4px) !important;
        border: 1px solid rgba(0, 0, 0, 0.37) !important;
    }
}