refactor: wrap DownloadManager content in a Container component for improved layout and styling

src/components/downloads/DownloadManager.tsx

@@ -13,6 +13,7 @@ import Link from "next/link";
 import { BookOfflineButton } from "@/components/ui/book-offline-button";
 import { useTranslate } from "@/hooks/useTranslate";
 import logger from "@/lib/logger";
+import { Container } from "@/components/ui/container";
 
 type BookStatus = "idle" | "downloading" | "available" | "error";
 
@@ -150,8 +151,9 @@ export function DownloadManager() {
   }
 
   return (
-    <>
-      <div className="container mx-auto px-4 py-8 space-y-12">
+    <Container>
+      <div className="space-y-6">
+        <div className="space-y-2">
           <h1 className="text-3xl font-bold tracking-tight">{t("downloads.page.title")}</h1>
           {t("downloads.page.description") && (
             <p className="text-lg text-muted-foreground">{t("downloads.page.description")}</p>
@@ -269,7 +271,8 @@ export function DownloadManager() {
           )}
         </TabsContent>
       </Tabs>
-    </>
+      </div>
+    </Container>
   );
 }