Three pieces: the simplified mark, the name of the section you are actually in, and the member's initials. The section name is written by a scroll spy, so the bar always says where you are rather than repeating the site's name back at you.
The lime rule is load-bearing. The bar and a navy hero carry the same weave, so without it the band has no edge and the two patterns run together. It also bookends the rule above the footer.
The nav is gone, not collapsed into a hamburger. A phone layout has a tab bar; that is the navigation, so the bar keeps only the three pieces.
Give the bar data-field-fixed if it also carries .field: a sticky element slides over the content and can never stay in register with it.
Hide on scroll down with .is-away and restore on scroll up. Never hide it on desktop, where the pointer has no other way back.