diff --git a/apps/readest-app/src/store/themeStore.ts b/apps/readest-app/src/store/themeStore.ts
index 24bb591a..a61d67c5 100644
--- a/apps/readest-app/src/store/themeStore.ts
+++ b/apps/readest-app/src/store/themeStore.ts
@@ -169,6 +169,9 @@ export const initSystemThemeListener = (appService: AppService) => {
     } else {
       systemIsDarkMode = mediaQuery.matches;
     }
+    if (typeof window !== 'undefined' && localStorage) {
+      localStorage.setItem('systemIsDarkMode', systemIsDarkMode ? 'true' : 'false');
+    }
     useThemeStore.getState().handleSystemThemeChange(systemIsDarkMode);
   };
 
diff --git a/apps/readest-app/src/utils/style.ts b/apps/readest-app/src/utils/style.ts
index 42280ca0..33fbf732 100644
--- a/apps/readest-app/src/utils/style.ts
+++ b/apps/readest-app/src/utils/style.ts
@@ -553,8 +553,8 @@ export const getThemeCode = () => {
   if (typeof window !== 'undefined') {
     themeColor = localStorage.getItem('themeColor') || 'default';
     themeMode = localStorage.getItem('themeMode') || 'auto';
+    systemIsDarkMode = localStorage.getItem('systemIsDarkMode') === 'true';
     customThemes = JSON.parse(localStorage.getItem('customThemes') || '[]');
-    systemIsDarkMode = window.matchMedia('(prefers-color-scheme: dark)').matches;
   }
   const isDarkMode = themeMode === 'dark' || (themeMode === 'auto' && systemIsDarkMode);
   let currentTheme = themes.find((theme) => theme.name === themeColor);