Hey Tom,
Header has a complex structure, there is no easy way to do this with CSS. It largely depends upon the Navbar height (Theme Options > Header > Navbar Top Height) and the logo height. If both are same then it can be achieved with flexbox. To simulate that you can try adding the following code in the Theme Options > CSS:
.x-navbar .desktop .x-nav > li > a {
display: flex;
align-items: center;
}
.x-navbar-static-active .x-navbar .desktop .x-nav>li>a>span, .x-navbar-fixed-top-active .x-navbar .desktop .x-nav>li>a>span {
margin-top: 0 !important;
}
.x-brand img {
max-height: 80px;
}
Now with the above CSS, set the navbar top link alignment to 0. Don’t forget to clear all caches including your browser’s cache after adding the code. Let us know how this goes!