Merge pull request #224 from floyd-li/master

fix: dark mode toggle

src/App.vue

@@ -20,7 +20,7 @@ const { wsCache } = useCache()
 
 // 根据浏览器当前主题设置系统主题色
 const setDefaultTheme = () => {
-  if (wsCache.get('isDark')) {
+  if (wsCache.get('isDark') !== null) {
     appStore.setIsDark(wsCache.get('isDark'))
     return
   }