Header

Appearance → Customize → Header. Three settings, all of them about where the identity and the menu sit against each other.

Header layout

• Inline — the logo and title on the left, the menu on the right, on one line. This is the default.
• Stack — the identity on its own line with the menu underneath it.

Stack suits a long site title or a menu with more than a handful of items, since neither has to share a line.

Vertical align

Only applies to the Inline layout, where the two sides can differ in height. Top, Middle or Bottom — which edge the menu lines up with against a taller logo block. Middle is the default.

Header width

• Full — the header spans the window, so the menu sits out at the edges while the text below it stays in its column. The default.
• Narrow — the header is held to the same reading width as the content, so the whole page reads as one column.

The menu

The header menu is an ordinary WordPress menu. Build it at Appearance → Menus — or in the Customizer under Menus — and assign it to the primary location. Setup creates one for you.

Menu links are never underlined at rest whatever the link style says, and the item for the page you are on always steps back so the current place is legible without color alone.