perf: 优化代码

src/components/navbar/index.vue

@@ -243,10 +243,10 @@ const showCheckInDialog = shallowRef<boolean>(false);
 
 const isDark = useDark({
   selector: 'body',
-  attribute: 'arco-theme',
+  attribute: 'site-theme',
   valueDark: 'dark',
   valueLight: 'light',
-  storageKey: 'arco-theme',
+  storageKey: 'site-theme',
   onChanged(dark: boolean) {
     // overridden default behavior
     appStore.toggleTheme(dark);