feat(ui): warm library palette (zinc+emerald -> stone+amber) with hover/focus feedback; text reader gains paper/sepia/night themes + persisted font-size (lib/readerPrefs.ts), serif justified measure; PDF drops emoji icons for 首页/末页, CBZ pill page counter, EPUB centered spread, blur reader header with format badge, aria labels on login/search/chapter select

frontend/src/components/TopBar.tsx

@@ -6,23 +6,29 @@ import { btn } from "./ui";
 export function TopBar({ right }: { right?: ReactNode }) {
   const { user, isAdmin, logout } = useAuth();
   return (
-    <header className="flex shrink-0 items-center gap-4 border-b border-zinc-800 px-4 py-3">
-      <Link to="/" className="font-semibold">
-        BookLib
+    <header className="flex shrink-0 items-center gap-2 border-b border-stone-800/80 px-4 py-3">
+      <Link to="/" className="font-serif text-lg font-semibold tracking-wide">
+        Book<span className="text-amber-500">Lib</span>
       </Link>
       {isAdmin && (
-        <Link className="text-sm text-zinc-400 hover:text-zinc-100" to="/admin/users">
+        <Link
+          className="rounded-md px-2 py-1 text-sm text-stone-400 transition-colors hover:bg-stone-800 hover:text-stone-100"
+          to="/admin/users"
+        >
           用户
         </Link>
       )}
       {isAdmin && (
-        <Link className="text-sm text-zinc-400 hover:text-zinc-100" to="/admin/libraries">
+        <Link
+          className="rounded-md px-2 py-1 text-sm text-stone-400 transition-colors hover:bg-stone-800 hover:text-stone-100"
+          to="/admin/libraries"
+        >
           库管理
         </Link>
       )}
       <div className="ml-auto flex items-center gap-3">
         {right}
-        <span className="text-sm text-zinc-400">
+        <span className="text-sm text-stone-400">
           {user?.username}
           {isAdmin ? "(admin)" : ""}
         </span>