Site header + nav
The sample has no current link. On a real page, the current link is underlined in the accent.
Markup contract
header.site-header > .wrapper > .site-header__inner > .site-header__name + nav > ul.site-header__links.
The current page link gets aria-current="page". Work gets aria-current="true" on case pages.
The header is full width and .wrapper sits inside it, so its background reaches both edges of the window.
On a real page site-header.js sets data-reveal, and data-hidden on the way down.