feat: 优化主题切换逻辑，添加浅色主题支持，更新相关样式

src/composables/useTheme.ts

@@ -1,5 +1,3 @@
-import { usePreferredDark } from "@vueuse/core";
-
 export type ThemeMode = "light" | "dark" | "auto";
 
 const STORAGE_KEY = "app-theme-mode";
@@ -16,7 +14,14 @@ export function useTheme() {
   });
 
   watch(isDark, (dark) => {
+    if (dark) {
       document.documentElement.classList.toggle("ion-palette-dark", dark);
+      document.documentElement.classList.remove("ion-palette-light");
+    }
+    else {
+      document.documentElement.classList.remove("ion-palette-dark");
+      document.documentElement.classList.add("ion-palette-light");
+    }
   }, { immediate: true });
 
   return {

src/store/user.ts

@@ -14,7 +14,7 @@ export const useUserStore = defineStore("user", () => {
     userProfile: null,
   });
 
-  const isAuthenticated = computed(() => token.value !== null);
+  const isAuthenticated = computed(() => !!token.value);
 
   async function updateProfile() {
     const { data } = await safeClient(client.api.user.profile.get(), { silent: true });

src/theme/variables.css

@@ -1,6 +1,6 @@
 /* For information on how to create your own theme, please refer to:
 http://ionicframework.com/docs/theming/ */
-html:root {
+html.ion-palette-light {
   --ion-color-primary: #0d0d0d;
   --ion-color-primary-rgb: 13, 13, 13;
   --ion-color-primary-contrast: #ffffff;