I saw a lot of sites with too many styles -or- not exactly vertically center nav links/ hamburger menu).
One way to solve this (less than a minute):
Desktop
1/3. display flex
Create a wrapper for brand/nav menu/menu button(hamburger). Set this wrapper to display flex and v-align.
2/3. margin auto
Webflow original nav-menu set to float: right; (Wont work so well with flexbox).
How to solve this?
Select nav-menu and set margin-left: auto (for RTL sites use margin-right: auto; ).
video:
3/3. tablet/mobile:
Select the hamburger menu - and again use margin-left: auto;
Done 
For perfect align center-center
Use margin-left: auto; margin-right: auto;
