The header is now three equal sections — navigation tabs (left), the
search field (center, so it lands at the window center), and the user
element (right) — fixing the tabs stretching to full width under the
search field.
- Nav tabs regain Lucide icons (compass, library, hard-drive,
cassette-tape) and use a 12px label.
- The user element uses a hamburger icon instead of the QBZ logo, which
aliased badly as a scaled PNG.
- Responsive: below 1140px the tabs drop their icons; below 960px the
search field narrows to 70%.
cc