fix: 调整事件详情页面

src/layouts/MainLayout.js

@@ -30,12 +30,12 @@ const MemoizedAppFooter = memo(AppFooter);
  */
 export default function MainLayout() {
     return (
-        <Box flex="1" h="100vh" w="100%" position="relative" display="flex" flexDirection="column">
+        <Box flex="1" h="100vh" w="100%" position="relative" display="flex" flexDirection="column" bg="#1A202C">
             {/* 导航栏 - 在所有页面间共享，memo 后不会在路由切换时重新渲染 */}
             <MemoizedHomeNavbar />
 
             {/* 页面内容区域 - flex: 1 占据剩余空间，包含错误边界、懒加载 */}
-            <Box flex="1" pt="60px">
+            <Box flex="1" pt="60px" bg="#1A202C">
                 <ErrorBoundary>
                     <Suspense fallback={<PageLoader message="页面加载中..." />}>
                         <Outlet />