Rebuilt all shared layout components from scratch using exact UBOLD v7.1.0 HTML structure. Files: sidebar.v7.php (sidenav-menu, logo, scrollbar, side-nav), topbar.php (app-topbar, topbar-item/topbar-link, badge-circle, theme switcher with __UBOLD_CONFIG__), menu_administration.php (side-nav-item/side-nav-link with BS5 collapse), menu_modules.php (v7 collapse/sub-menu with SubMenusV7 helpers). Dark mode seamless - sidebar logo synced with topbar bg. All old files backed up as filename-bk.ext. Zero PHP errors.