/* Light/dark mode: the top nav bar (.brand-nav) deliberately stays a fixed dark color in both themes — it already uses btn-outline-light/dropdown-menu throughout, and re-verifying every one of those against a light background across all pages isn't worth it for a toolbar that reads fine dark either way. Only the page content (cards, tables, body) actually switches, driven by these variables + the [data-bs-theme] selector set on by theme.js. IMPORTANT: a fixed-dark background alone isn't enough — Bootstrap's own .nav-link/.navbar-brand text color follows the nearest data-bs-theme ancestor, which in light mode meant dark text on this still-dark background (invisible). Fixed by putting data-bs-theme="dark" directly on the