Visibility polish: admin sidebar contrast/focus, table header readability, nav focus rings

src/components/admin/admin-mobile-wrapper.tsx

@@ -36,8 +36,9 @@ export function AdminMobileWrapper({
 				<button
 					type="button"
 					onClick={() => setOpen(!open)}
-					className="flex items-center justify-center w-9 h-9 rounded-lg"
-					style={{ color: "var(--admin-text-muted)" }}
+					className="flex items-center justify-center w-9 h-9 rounded-lg
+						focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-[var(--admin-accent)] focus-visible:ring-offset-1 focus-visible:ring-offset-[var(--admin-sidebar-background)]"
+					style={{ color: "var(--admin-sidebar-text-readable)" }}
 				>
 					{open ? <X size={18} /> : <Menu size={18} />}
 				</button>

src/components/admin/admin-nav-link.tsx

@@ -28,11 +28,12 @@ export function AdminNavLink({
 		<Link
 			href={href}
 			aria-current={active ? "page" : undefined}
-			className={`group flex items-center gap-2.5 rounded-xl px-3 py-2 text-sm no-underline transition-all duration-150 ${
-				active
-					? "bg-[var(--admin-accent)]/20 font-semibold text-[var(--admin-sidebar-text-readable)] border-l-2 border-[var(--admin-accent)] shadow-sm"
-					: "font-medium text-[var(--admin-sidebar-text-readable)] hover:bg-[var(--admin-accent)]/10 hover:no-underline"
-			}`}
+			className={`group flex items-center gap-2.5 rounded-xl px-3 py-2 text-sm no-underline transition-colors duration-150
+				focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-[var(--admin-accent)] focus-visible:ring-offset-1 focus-visible:ring-offset-[var(--admin-sidebar-background)] ${
+					active
+						? "bg-[var(--admin-accent)]/25 font-semibold text-[var(--admin-sidebar-text-readable)] border-l-2 border-[var(--admin-accent)] shadow-sm"
+						: "font-medium text-[var(--admin-sidebar-text-readable)] hover:bg-[var(--admin-accent)]/10 hover:no-underline"
+				}`}
 		>
 			{icon ? (
 				<span