diff --git a/app/pages/500.vue b/app/pages/500.vue
index 66184ef..6b4ddcf 100644
--- a/app/pages/500.vue
+++ b/app/pages/500.vue
@@ -1,5 +1,14 @@
 <template>
-  <div class="error-page">
+  <div class="error-page" :class="{ 'dark-mode': isDarkMode }">
+    <!-- macOS Style Background -->
+    <div class="background-image">
+      <div class="blur-overlay"></div>
+      <div class="gradient-overlay"></div>
+    </div>
+
+    <!-- Glass Layer -->
+    <div class="glass-layer"></div>
+
     <!-- Windows-style Error Window -->
     <div class="error-window">
       <!-- Title Bar -->
@@ -30,68 +39,76 @@
             <p class="error-description">{{ $t('error.serverErrorDescription') }}</p>
           </div>
 
-          <!-- Action Buttons -->
+          <!-- Action Button -->
           <div class="error-actions">
             <button class="action-btn primary" @click="goHome">
               <span class="btn-icon">🏠</span>
               {{ $t('error.goHome') }}
             </button>
-            <button class="action-btn secondary" @click="refreshPage">
-              <span class="btn-icon">🔄</span>
-              {{ $t('error.refresh') }}
-            </button>
-            <button class="action-btn secondary" @click="reportError">
-              <span class="btn-icon">📧</span>
-              {{ $t('error.report') }}
-            </button>
-          </div>
-
-          <!-- Technical Details (Collapsible) -->
-          <div class="technical-details">
-            <button class="details-toggle" @click="toggleDetails">
-              <span class="toggle-icon" :class="{ 'rotated': showDetails }">▼</span>
-              {{ $t('error.technicalDetails') }}
-            </button>
-            <div v-if="showDetails" class="details-content">
-              <div class="details-item">
-                <strong>{{ $t('error.errorCode') }}:</strong> 500 - Internal Server Error
-              </div>
-              <div class="details-item">
-                <strong>{{ $t('error.timestamp') }}:</strong> {{ currentTime }}
-              </div>
-              <div class="details-item">
-                <strong>{{ $t('error.requestId') }}:</strong> {{ requestId }}
-              </div>
-              <div class="details-item">
-                <strong>{{ $t('error.userAgent') }}:</strong> {{ userAgent }}
-              </div>
-            </div>
           </div>
         </div>
       </div>
     </div>
 
-    <!-- Background Pattern -->
-    <div class="error-background">
-      <div class="pattern-grid"></div>
+    <!-- Status Bar -->
+    <div class="status-bar">
+      <div class="status-left">
+        <!-- Empty for now -->
+      </div>
+      <div class="status-center">
+        <!-- Empty for now -->
+      </div>
+      <div class="status-right">
+        <!-- Language Toggle -->
+        <div class="language-switcher-wrapper" ref="languageSwitcherWrapper">
+          <button @click="toggleLanguageMenu" class="language-switcher">
+            {{ currentLanguageDisplay }}
+          </button>
+          <div v-if="isLanguageMenuOpen" class="language-menu">
+            <ul>
+              <li v-for="lang in availableLanguages" :key="lang.key" @click="selectLanguage(lang.key as 'en' | 'zh')">
+                <span class="checkmark" :style="{ visibility: locale === lang.key ? 'visible' : 'hidden' }">✓</span>
+                <span>{{ lang.label }}</span>
+              </li>
+            </ul>
+          </div>
+        </div>
+      </div>
     </div>
   </div>
 </template>
 
 <script setup lang="ts">
-import { ref, computed, onMounted } from 'vue';
+import { ref, computed, onMounted, onUnmounted, watch } from 'vue';
 import { useRouter } from 'vue-router';
 import { useI18n } from 'vue-i18n';
+import { useSettingsStore } from '../../stores/settings';
 
 const router = useRouter();
-const { t } = useI18n();
+const { t, locale, setLocale } = useI18n();
+const settingsStore = useSettingsStore();
 
 // Reactive state
-const showDetails = ref(false);
 const currentTime = ref('');
 const requestId = ref('');
 const userAgent = ref('');
 
+// --- Language Switcher Logic ---
+const isLanguageMenuOpen = ref(false);
+const languageSwitcherWrapper = ref<HTMLElement | null>(null);
+const availableLanguages = computed(() => [
+  { key: 'en', label: 'English', display: 'EN' },
+  { key: 'zh', label: '繁體中文', display: '注' },
+]);
+
+const currentLanguageDisplay = computed(() => {
+  const current = availableLanguages.value.find(lang => lang.key === locale.value);
+  return current?.display || '注';
+});
+
+// Theme state from settings store
+const isDarkMode = computed(() => settingsStore.theme === 'dark');
+
 // Computed properties
 const goHome = () => {
   router.push('/');
@@ -107,8 +124,20 @@ const reportError = () => {
   alert(t('error.reportSent'));
 };
 
-const toggleDetails = () => {
-  showDetails.value = !showDetails.value;
+// Language switcher functions
+function toggleLanguageMenu() {
+  isLanguageMenuOpen.value = !isLanguageMenuOpen.value;
+}
+
+function selectLanguage(lang: 'en' | 'zh') {
+  setLocale(lang);
+  isLanguageMenuOpen.value = false;
+}
+
+const handleClickOutside = (event: MouseEvent) => {
+  if (languageSwitcherWrapper.value && !languageSwitcherWrapper.value.contains(event.target as Node)) {
+    isLanguageMenuOpen.value = false;
+  }
 };
 
 // Initialize data
@@ -118,6 +147,19 @@ onMounted(() => {
   userAgent.value = navigator.userAgent.substring(0, 50) + '...';
 });
 
+onUnmounted(() => {
+  document.removeEventListener('click', handleClickOutside);
+});
+
+// Watch for language menu state
+watch(isLanguageMenuOpen, (isOpen) => {
+  if (isOpen) {
+    document.addEventListener('click', handleClickOutside);
+  } else {
+    document.removeEventListener('click', handleClickOutside);
+  }
+});
+
 // Set page title
 useHead({
   title: t('error.title')
@@ -131,7 +173,6 @@ useHead({
   left: 0;
   width: 100vw;
   height: 100vh;
-  background: var(--background-desktop);
   display: flex;
   align-items: center;
   justify-content: center;
@@ -139,34 +180,68 @@ useHead({
   overflow: hidden;
 }
 
-.error-background {
+.background-image {
   position: absolute;
   top: 0;
   left: 0;
   width: 100%;
   height: 100%;
-  opacity: 0.1;
+  background: linear-gradient(135deg, 
+    #f8fafc 0%, 
+    #e2e8f0 25%, 
+    #cbd5e1 50%, 
+    #94a3b8 75%, 
+    #64748b 100%);
+  background-size: 400% 400%;
+  animation: gradient-shift 15s ease infinite;
   z-index: 0;
 }
 
-.pattern-grid {
+.glass-layer {
+  position: absolute;
+  top: 0;
+  left: 0;
   width: 100%;
   height: 100%;
-  background-image: 
-    linear-gradient(rgba(255, 255, 255, 0.1) 1px, transparent 1px),
-    linear-gradient(90deg, rgba(255, 255, 255, 0.1) 1px, transparent 1px);
-  background-size: 20px 20px;
-  animation: grid-move 20s linear infinite;
+  background: rgba(255, 255, 255, 0.1);
+  backdrop-filter: blur(20px);
+  -webkit-backdrop-filter: blur(20px);
+  z-index: 1;
 }
 
-@keyframes grid-move {
-  0% { transform: translate(0, 0); }
-  100% { transform: translate(20px, 20px); }
+@keyframes gradient-shift {
+  0% { background-position: 0% 50%; }
+  50% { background-position: 100% 50%; }
+  100% { background-position: 0% 50%; }
+}
+
+.blur-overlay {
+  position: absolute;
+  top: 0;
+  left: 0;
+  width: 100%;
+  height: 100%;
+  backdrop-filter: blur(20px);
+  -webkit-backdrop-filter: blur(20px);
+}
+
+.gradient-overlay {
+  position: absolute;
+  top: 0;
+  left: 0;
+  width: 100%;
+  height: 100%;
+  background: linear-gradient(
+    180deg,
+    rgba(0, 0, 0, 0.1) 0%,
+    rgba(0, 0, 0, 0.3) 50%,
+    rgba(0, 0, 0, 0.6) 100%
+  );
 }
 
 .error-window {
   position: relative;
-  z-index: 1;
+  z-index: 2;
   width: 90%;
   max-width: 600px;
   background: var(--window-background);
@@ -304,10 +379,8 @@ useHead({
 
 .error-actions {
   display: flex;
-  gap: 12px;
   justify-content: center;
   margin-bottom: 32px;
-  flex-wrap: wrap;
 }
 
 .action-btn {
@@ -352,56 +425,92 @@ useHead({
   font-size: 16px;
 }
 
-.technical-details {
-  border-top: 1px solid var(--window-border-color);
-  padding-top: 20px;
+
+.status-bar {
+  position: absolute;
+  top: 0;
+  left: 0;
+  right: 0;
+  height: 22px;
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  padding: 0 20px;
+  background: var(--taskbar-background);
+  backdrop-filter: blur(20px);
+  -webkit-backdrop-filter: blur(20px);
+  color: var(--taskbar-item-text-color);
+  font-size: 12px;
+  font-weight: 500;
+  z-index: 2;
+  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
 }
 
-.details-toggle {
-  background: none;
-  border: none;
-  color: var(--content-text-color);
-  cursor: pointer;
-  font-size: 14px;
+.status-left,
+.status-center,
+.status-right {
   display: flex;
   align-items: center;
   gap: 8px;
-  margin: 0 auto;
-  padding: 8px;
-  border-radius: var(--rounded-button);
-  transition: background-color 0.2s ease;
 }
 
-.details-toggle:hover {
-  background: var(--taskbar-item-background);
+.language-switcher-wrapper {
+  position: relative;
 }
 
-.toggle-icon {
-  transition: transform 0.3s ease;
+.language-switcher {
+  background: none;
+  border: none;
+  color: var(--taskbar-item-text-color);
   font-size: 12px;
+  font-weight: 500;
+  cursor: pointer;
+  padding: 0 4px;
+  width: 24px;
+  height: 22px;
+  text-align: center;
+  line-height: 22px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
 }
 
-.toggle-icon.rotated {
-  transform: rotate(180deg);
+.language-menu {
+  position: absolute;
+  top: calc(100% + 4px);
+  right: 0;
+  width: 160px;
+  background-color: var(--start-menu-background);
+  border: 1px solid var(--start-menu-border-color);
+  border-radius: 8px;
+  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
+  padding: 4px;
+  z-index: 10001;
 }
 
-.details-content {
-  margin-top: 16px;
-  padding: 16px;
-  background: var(--taskbar-item-background);
-  border-radius: var(--rounded-button);
-  text-align: left;
-  font-size: 13px;
-  line-height: 1.5;
+.language-menu ul {
+  list-style: none;
+  padding: 0;
+  margin: 0;
 }
 
-.details-item {
-  margin-bottom: 8px;
-  word-break: break-all;
+.language-menu li {
+  display: flex;
+  align-items: center;
+  padding: 4px 8px;
+  border-radius: 4px;
+  cursor: pointer;
+  transition: background-color 0.15s ease-in-out;
 }
 
-.details-item:last-child {
-  margin-bottom: 0;
+.language-menu li:hover {
+  background-color: var(--taskbar-item-background-hover);
+}
+
+.checkmark {
+  width: 16px;
+  text-align: center;
+  margin-right: 4px;
 }
 
 /* Responsive Design */
@@ -423,27 +532,164 @@ useHead({
     font-size: 24px;
   }
   
-  .error-actions {
-    flex-direction: column;
-    align-items: center;
-  }
-  
   .action-btn {
     width: 100%;
     max-width: 200px;
   }
+  
+  .status-bar {
+    padding: 8px 16px;
+    font-size: 0.8rem;
+  }
 }
 
-/* Dark/Light theme transitions */
-.error-page {
-  transition: background-color 0.3s ease;
+/* Light mode (default) */
+.background-image {
+  background: linear-gradient(135deg, 
+    #f8fafc 0%, 
+    #e2e8f0 25%, 
+    #cbd5e1 50%, 
+    #94a3b8 75%, 
+    #64748b 100%);
+}
+
+.glass-layer {
+  background: rgba(255, 255, 255, 0.1);
 }
 
 .error-window {
-  transition: background-color 0.3s ease, border-color 0.3s ease;
+  background: rgba(255, 255, 255, 0.95);
+  border: 1px solid rgba(255, 255, 255, 0.2);
+  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
+}
+
+.title-bar {
+  background: rgba(255, 255, 255, 0.9);
+  color: #1f2937;
+  border-bottom: 1px solid rgba(0, 0, 0, 0.1);
 }
 
 .window-content {
-  transition: color 0.3s ease;
+  color: #1f2937;
+}
+
+.error-title {
+  color: #1f2937;
+}
+
+.error-description {
+  color: #4b5563;
+}
+
+.action-btn.primary {
+  background: #10b981;
+  color: white;
+}
+
+.action-btn.primary:hover {
+  background: #059669;
+  box-shadow: 0 6px 20px rgba(16, 185, 129, 0.4);
+}
+
+.action-btn.secondary {
+  background: rgba(0, 0, 0, 0.05);
+  color: #374151;
+  border: 1px solid rgba(0, 0, 0, 0.1);
+}
+
+.action-btn.secondary:hover {
+  background: rgba(0, 0, 0, 0.1);
+}
+
+.details-toggle {
+  color: #374151;
+}
+
+.details-toggle:hover {
+  background: rgba(0, 0, 0, 0.05);
+}
+
+.details-content {
+  background: rgba(0, 0, 0, 0.05);
+  border: 1px solid rgba(0, 0, 0, 0.1);
+}
+
+.details-item {
+  color: #4b5563;
+}
+
+/* Dark mode adjustments */
+.dark-mode .background-image {
+  background: linear-gradient(135deg, 
+    #0f172a 0%, 
+    #1e293b 25%, 
+    #334155 50%, 
+    #475569 75%, 
+    #64748b 100%);
+}
+
+.dark-mode .glass-layer {
+  background: rgba(0, 0, 0, 0.1);
+}
+
+.dark-mode .error-window {
+  background: rgba(15, 23, 42, 0.95);
+  border: 1px solid rgba(255, 255, 255, 0.1);
+  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
+}
+
+.dark-mode .title-bar {
+  background: rgba(15, 23, 42, 0.9);
+  color: #f1f5f9;
+  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
+}
+
+.dark-mode .window-content {
+  color: #f1f5f9;
+}
+
+.dark-mode .error-title {
+  color: #f1f5f9;
+}
+
+.dark-mode .error-description {
+  color: #cbd5e1;
+}
+
+.dark-mode .action-btn.primary {
+  background: #10b981;
+  color: white;
+}
+
+.dark-mode .action-btn.primary:hover {
+  background: #059669;
+  box-shadow: 0 6px 20px rgba(16, 185, 129, 0.4);
+}
+
+.dark-mode .action-btn.secondary {
+  background: rgba(255, 255, 255, 0.1);
+  color: #e2e8f0;
+  border: 1px solid rgba(255, 255, 255, 0.2);
+}
+
+.dark-mode .action-btn.secondary:hover {
+  background: rgba(255, 255, 255, 0.2);
+}
+
+.dark-mode .details-toggle {
+  color: #e2e8f0;
+}
+
+.dark-mode .details-toggle:hover {
+  background: rgba(255, 255, 255, 0.1);
+}
+
+.dark-mode .details-content {
+  background: rgba(255, 255, 255, 0.1);
+  border: 1px solid rgba(255, 255, 255, 0.2);
+}
+
+.dark-mode .details-item {
+  color: #cbd5e1;
 }
 </style>
diff --git a/app/pages/register.vue b/app/pages/register.vue
index 09687a3..64224eb 100644
--- a/app/pages/register.vue
+++ b/app/pages/register.vue
@@ -1,138 +1,149 @@
 <template>
-  <div class="auth-page">
-    <!-- Windows-style Auth Window -->
-    <div class="auth-window">
-      <!-- Title Bar -->
-      <div class="title-bar">
-        <div class="title-bar-content">
-          <div class="title-bar-icon">📝</div>
-          <div class="title-bar-text">{{ $t('auth.register.title') }}</div>
-        </div>
-        <div class="title-bar-controls">
-          <button class="control-btn close-btn" @click="goHome">
-            <span class="control-btn-icon">×</span>
-          </button>
-        </div>
+  <div class="setup-screen">
+    <!-- macOS Style Background -->
+    <div class="background-image">
+      <div class="blur-overlay"></div>
+      <div class="gradient-overlay"></div>
+    </div>
+
+    <!-- Glass Layer -->
+    <div class="glass-layer"></div>
+
+    <!-- Setup Content -->
+    <div class="setup-content">
+      <!-- Setup Header -->
+      <div class="setup-header">
+        <div class="setup-icon">👤</div>
+        <h1 class="setup-title">{{ $t('auth.register.title') }}</h1>
+        <p class="setup-subtitle">{{ $t('auth.register.subtitle') }}</p>
       </div>
 
-      <!-- Window Content -->
-      <div class="window-content">
-        <div class="auth-content">
-          <!-- Header -->
-          <div class="auth-header">
-            <h1 class="auth-title">{{ $t('auth.register.title') }}</h1>
-            <p class="auth-subtitle">{{ $t('auth.register.subtitle') }}</p>
+      <!-- Setup Form -->
+      <div class="setup-form">
+        <form @submit.prevent="handleRegister" class="form">
+          <!-- Full Name Field -->
+          <div class="form-field">
+            <input
+              v-model="form.fullName"
+              type="text"
+              :placeholder="$t('auth.register.fullNamePlaceholder')"
+              class="setup-input"
+              :class="{ 'error': errors.fullName }"
+              required
+            />
           </div>
 
-          <!-- Form -->
-          <form @submit.prevent="handleRegister" class="auth-form">
-            <!-- Full Name Field -->
-            <div class="form-group">
-              <label for="fullName" class="form-label">{{ $t('auth.register.fullName') }}</label>
-              <input
-                id="fullName"
-                v-model="form.fullName"
-                type="text"
-                :placeholder="$t('auth.register.fullNamePlaceholder')"
-                class="form-input"
-                :class="{ 'error': errors.fullName }"
-                required
-              />
-              <span v-if="errors.fullName" class="error-message">{{ errors.fullName }}</span>
-            </div>
+          <!-- Email Field -->
+          <div class="form-field">
+            <input
+              v-model="form.email"
+              type="email"
+              :placeholder="$t('auth.register.emailPlaceholder')"
+              class="setup-input"
+              :class="{ 'error': errors.email }"
+              required
+            />
+          </div>
 
-            <!-- Email Field -->
-            <div class="form-group">
-              <label for="email" class="form-label">{{ $t('auth.register.email') }}</label>
-              <input
-                id="email"
-                v-model="form.email"
-                type="email"
-                :placeholder="$t('auth.register.emailPlaceholder')"
-                class="form-input"
-                :class="{ 'error': errors.email }"
-                required
-              />
-              <span v-if="errors.email" class="error-message">{{ errors.email }}</span>
-            </div>
+          <!-- Password Field -->
+          <div class="form-field">
+            <input
+              v-model="form.password"
+              type="password"
+              :placeholder="$t('auth.register.passwordPlaceholder')"
+              class="setup-input"
+              :class="{ 'error': errors.password }"
+              required
+            />
+          </div>
 
-            <!-- Password Field -->
-            <div class="form-group">
-              <label for="password" class="form-label">{{ $t('auth.register.password') }}</label>
-              <input
-                id="password"
-                v-model="form.password"
-                type="password"
-                :placeholder="$t('auth.register.passwordPlaceholder')"
-                class="form-input"
-                :class="{ 'error': errors.password }"
-                required
-              />
-              <span v-if="errors.password" class="error-message">{{ errors.password }}</span>
-            </div>
+          <!-- Confirm Password Field -->
+          <div class="form-field">
+            <input
+              v-model="form.confirmPassword"
+              type="password"
+              :placeholder="$t('auth.register.confirmPasswordPlaceholder')"
+              class="setup-input"
+              :class="{ 'error': errors.confirmPassword }"
+              required
+            />
+          </div>
 
-            <!-- Confirm Password Field -->
-            <div class="form-group">
-              <label for="confirmPassword" class="form-label">{{ $t('auth.register.confirmPassword') }}</label>
-              <input
-                id="confirmPassword"
-                v-model="form.confirmPassword"
-                type="password"
-                :placeholder="$t('auth.register.confirmPasswordPlaceholder')"
-                class="form-input"
-                :class="{ 'error': errors.confirmPassword }"
-                required
-              />
-              <span v-if="errors.confirmPassword" class="error-message">{{ errors.confirmPassword }}</span>
-            </div>
+          <!-- Terms and Conditions -->
+          <div class="terms-section">
+            <label class="terms-label">
+              <input v-model="form.agreeTerms" type="checkbox" class="terms-checkbox" required />
+              <span class="terms-text">
+                {{ $t('auth.register.agreeTerms') }}
+                <button type="button" class="terms-link" @click="showTerms">
+                  {{ $t('auth.register.termsAndConditions') }}
+                </button>
+              </span>
+            </label>
+          </div>
 
-            <!-- Terms and Conditions -->
-            <div class="form-group">
-              <label class="checkbox-label">
-                <input v-model="form.agreeTerms" type="checkbox" class="checkbox-input" required />
-                <span class="checkbox-text">
-                  {{ $t('auth.register.agreeTerms') }}
-                  <button type="button" class="terms-link" @click="showTerms">
-                    {{ $t('auth.register.termsAndConditions') }}
-                  </button>
-                </span>
-              </label>
-            </div>
+          <!-- Unified Error Messages -->
+          <div class="error-messages">
+            <div v-if="errors.fullName" class="error-message">{{ errors.fullName }}</div>
+            <div v-if="errors.email" class="error-message">{{ errors.email }}</div>
+            <div v-if="errors.password" class="error-message">{{ errors.password }}</div>
+            <div v-if="errors.confirmPassword" class="error-message">{{ errors.confirmPassword }}</div>
+          </div>
 
-            <!-- Submit Button -->
-            <button type="submit" class="auth-button" :disabled="isLoading">
-              <span v-if="isLoading" class="loading-spinner"></span>
-              {{ isLoading ? $t('auth.common.loading') : $t('auth.register.registerButton') }}
+          <!-- Submit Button -->
+          <button type="submit" class="setup-button" :disabled="isLoading">
+            <span v-if="isLoading" class="loading-spinner"></span>
+            {{ isLoading ? $t('auth.common.loading') : $t('auth.register.registerButton') }}
+          </button>
+        </form>
+
+        <!-- Sign In Link -->
+        <div class="setup-footer">
+          <p class="footer-text">
+            {{ $t('auth.register.hasAccount') }}
+            <button class="footer-link" @click="goToLogin">
+              {{ $t('auth.register.signIn') }}
             </button>
-          </form>
-
-          <!-- Sign In Link -->
-          <div class="auth-footer">
-            <p class="auth-footer-text">
-              {{ $t('auth.register.hasAccount') }}
-              <button class="auth-link" @click="goToLogin">
-                {{ $t('auth.register.signIn') }}
-              </button>
-            </p>
-          </div>
+          </p>
         </div>
       </div>
     </div>
 
-    <!-- Background Pattern -->
-    <div class="auth-background">
-      <div class="pattern-grid"></div>
+    <!-- Status Bar -->
+    <div class="status-bar">
+      <div class="status-left">
+        <!-- Empty for now -->
+      </div>
+      <div class="status-center">
+        <!-- Empty for now -->
+      </div>
+      <div class="status-right">
+        <!-- Language Toggle -->
+        <div class="language-switcher-wrapper" ref="languageSwitcherWrapper">
+          <button @click="toggleLanguageMenu" class="language-switcher">
+            {{ currentLanguageDisplay }}
+          </button>
+          <div v-if="isLanguageMenuOpen" class="language-menu">
+            <ul>
+              <li v-for="lang in availableLanguages" :key="lang.key" @click="selectLanguage(lang.key as 'en' | 'zh')">
+                <span class="checkmark" :style="{ visibility: locale === lang.key ? 'visible' : 'hidden' }">✓</span>
+                <span>{{ lang.label }}</span>
+              </li>
+            </ul>
+          </div>
+        </div>
+      </div>
     </div>
   </div>
 </template>
 
 <script setup lang="ts">
-import { ref, reactive } from 'vue';
+import { ref, reactive, computed, onMounted, onUnmounted, watch } from 'vue';
 import { useRouter } from 'vue-router';
 import { useI18n } from 'vue-i18n';
 
 const router = useRouter();
-const { t } = useI18n();
+const { t, locale, setLocale } = useI18n();
 
 // Form data
 const form = reactive({
@@ -154,6 +165,19 @@ const errors = reactive({
 // Loading state
 const isLoading = ref(false);
 
+// --- Language Switcher Logic ---
+const isLanguageMenuOpen = ref(false);
+const languageSwitcherWrapper = ref<HTMLElement | null>(null);
+const availableLanguages = computed(() => [
+  { key: 'en', label: 'English', display: 'EN' },
+  { key: 'zh', label: '繁體中文', display: '注' },
+]);
+
+const currentLanguageDisplay = computed(() => {
+  const current = availableLanguages.value.find(lang => lang.key === locale.value);
+  return current?.display || '注';
+});
+
 // Validation functions
 const validateEmail = (email: string) => {
   const emailRegex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
@@ -233,204 +257,243 @@ const goToLogin = () => {
 const goHome = () => {
   router.push('/');
 };
+
+// Language switcher functions
+function toggleLanguageMenu() {
+  isLanguageMenuOpen.value = !isLanguageMenuOpen.value;
+}
+
+function selectLanguage(lang: 'en' | 'zh') {
+  setLocale(lang);
+  isLanguageMenuOpen.value = false;
+}
+
+const handleClickOutside = (event: MouseEvent) => {
+  if (languageSwitcherWrapper.value && !languageSwitcherWrapper.value.contains(event.target as Node)) {
+    isLanguageMenuOpen.value = false;
+  }
+};
+
+// Lifecycle
+onMounted(() => {
+  // Add any initialization logic here
+});
+
+onUnmounted(() => {
+  document.removeEventListener('click', handleClickOutside);
+});
+
+// Watch for language menu state
+watch(isLanguageMenuOpen, (isOpen) => {
+  if (isOpen) {
+    document.addEventListener('click', handleClickOutside);
+  } else {
+    document.removeEventListener('click', handleClickOutside);
+  }
+});
 </script>
 
 <style scoped>
-.auth-page {
+.setup-screen {
   position: fixed;
   top: 0;
   left: 0;
   width: 100vw;
   height: 100vh;
-  background: var(--background-desktop);
-  display: flex;
-  align-items: center;
-  justify-content: center;
-  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
+  font-family: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Helvetica Neue', Helvetica, Arial, sans-serif;
   overflow: hidden;
+  display: flex;
+  flex-direction: column;
 }
 
-.auth-background {
+.background-image {
   position: absolute;
   top: 0;
   left: 0;
   width: 100%;
   height: 100%;
-  opacity: 0.1;
+  background: linear-gradient(135deg, 
+    #f8fafc 0%, 
+    #e2e8f0 25%, 
+    #cbd5e1 50%, 
+    #94a3b8 75%, 
+    #64748b 100%);
+  background-size: 400% 400%;
+  animation: gradient-shift 15s ease infinite;
   z-index: 0;
 }
 
-.pattern-grid {
+.glass-layer {
+  position: absolute;
+  top: 0;
+  left: 0;
   width: 100%;
   height: 100%;
-  background-image: 
-    linear-gradient(rgba(255, 255, 255, 0.1) 1px, transparent 1px),
-    linear-gradient(90deg, rgba(255, 255, 255, 0.1) 1px, transparent 1px);
-  background-size: 20px 20px;
-  animation: grid-move 20s linear infinite;
-}
-
-@keyframes grid-move {
-  0% { transform: translate(0, 0); }
-  100% { transform: translate(20px, 20px); }
-}
-
-.auth-window {
-  position: relative;
+  background: rgba(255, 255, 255, 0.1);
+  backdrop-filter: blur(20px);
+  -webkit-backdrop-filter: blur(20px);
   z-index: 1;
-  width: 90%;
-  max-width: 400px;
-  background: var(--window-background);
-  border: 1px solid var(--window-border-color);
-  border-radius: var(--rounded-window);
-  box-shadow: var(--shadow-window);
-  overflow: hidden;
-  animation: window-appear 0.5s ease-out;
 }
 
-@keyframes window-appear {
-  from {
-    opacity: 0;
-    transform: scale(0.9) translateY(20px);
-  }
-  to {
-    opacity: 1;
-    transform: scale(1) translateY(0);
-  }
+@keyframes gradient-shift {
+  0% { background-position: 0% 50%; }
+  50% { background-position: 100% 50%; }
+  100% { background-position: 0% 50%; }
 }
 
-.title-bar {
-  display: flex;
-  align-items: center;
-  justify-content: space-between;
-  background: var(--title-bar-background);
-  color: var(--title-bar-text-color);
-  padding: 8px 12px;
-  border-bottom: 1px solid var(--window-border-color);
-}
-
-.title-bar-content {
-  display: flex;
-  align-items: center;
-  gap: 8px;
-}
-
-.title-bar-icon {
-  font-size: 16px;
-}
-
-.title-bar-text {
-  font-weight: 600;
-  font-size: 14px;
-}
-
-.title-bar-controls {
-  display: flex;
-  gap: 4px;
-}
-
-.control-btn {
-  width: 20px;
-  height: 20px;
-  border: none;
-  border-radius: var(--rounded-control-btn);
-  background: var(--control-btn-close-bg);
-  color: white;
-  display: flex;
-  align-items: center;
-  justify-content: center;
-  cursor: pointer;
-  transition: all 0.2s ease;
-  font-size: 12px;
-  font-weight: bold;
-}
-
-.control-btn:hover {
-  transform: scale(1.1);
-  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
-}
-
-.window-content {
-  padding: 32px;
-  color: var(--content-text-color);
-}
-
-.auth-content {
-  text-align: center;
-}
-
-.auth-header {
-  margin-bottom: 32px;
-}
-
-.auth-title {
-  font-size: 28px;
-  font-weight: 700;
-  margin-bottom: 8px;
-  color: var(--content-text-color);
-}
-
-.auth-subtitle {
-  font-size: 16px;
-  color: var(--content-text-color);
-  opacity: 0.7;
-}
-
-.auth-form {
-  text-align: left;
-}
-
-.form-group {
-  margin-bottom: 20px;
-}
-
-.form-label {
-  display: block;
-  font-size: 14px;
-  font-weight: 600;
-  margin-bottom: 8px;
-  color: var(--content-text-color);
-}
-
-.form-input {
+.blur-overlay {
+  position: absolute;
+  top: 0;
+  left: 0;
   width: 100%;
-  padding: 12px 16px;
-  border: 1px solid var(--window-border-color);
-  border-radius: var(--rounded-button);
-  background: var(--taskbar-item-background);
-  color: var(--content-text-color);
-  font-size: 14px;
+  height: 100%;
+  backdrop-filter: blur(20px);
+  -webkit-backdrop-filter: blur(20px);
+}
+
+.gradient-overlay {
+  position: absolute;
+  top: 0;
+  left: 0;
+  width: 100%;
+  height: 100%;
+  background: linear-gradient(
+    180deg,
+    rgba(0, 0, 0, 0.1) 0%,
+    rgba(0, 0, 0, 0.3) 50%,
+    rgba(0, 0, 0, 0.6) 100%
+  );
+}
+
+.setup-content {
+  position: relative;
+  z-index: 2;
+  flex: 1;
+  display: flex;
+  flex-direction: column;
+  justify-content: center;
+  align-items: center;
+  padding: 60px 40px 40px;
+  color: white;
+  min-height: 100vh;
+  box-sizing: border-box;
+}
+
+.setup-header {
+  text-align: center;
+  margin-bottom: 40px;
+  position: relative;
+  width: 100%;
+  display: flex;
+  flex-direction: column;
+  justify-content: center;
+  align-items: center;
+}
+
+.setup-icon {
+  font-size: 4rem;
+  margin-bottom: 20px;
+  filter: drop-shadow(0 2px 8px rgba(0, 0, 0, 0.3));
+}
+
+.setup-title {
+  font-size: 2.5rem;
+  font-weight: 300;
+  margin-bottom: 12px;
+  text-shadow: 0 2px 20px rgba(0, 0, 0, 0.3);
+  line-height: 1.2;
+}
+
+.setup-subtitle {
+  font-size: 1.2rem;
+  font-weight: 300;
+  opacity: 0.9;
+  text-shadow: 0 1px 10px rgba(0, 0, 0, 0.3);
+  line-height: 1.4;
+}
+
+.setup-form {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  gap: 20px;
+  position: relative;
+  width: 100%;
+  max-width: 400px;
+  justify-content: center;
+}
+
+.form {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  gap: 16px;
+  width: 100%;
+}
+
+.form-field {
+  width: 100%;
+  position: relative;
+}
+
+.setup-input {
+  width: 100%;
+  height: 50px;
+  padding: 14px 24px;
+  background: rgba(255, 255, 255, 0.15);
+  backdrop-filter: blur(20px);
+  border: 2px solid rgba(255, 255, 255, 0.3);
+  border-radius: 50px;
+  color: white;
+  font-size: 1rem;
+  font-weight: 300;
+  text-align: center;
+  outline: none;
+  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
   transition: all 0.3s ease;
   box-sizing: border-box;
 }
 
-.form-input:focus {
+.setup-input::placeholder {
+  color: rgba(255, 255, 255, 0.7);
+  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
+}
+
+.setup-input:focus {
+  background: rgba(255, 255, 255, 0.2);
+  border-color: rgba(255, 255, 255, 0.5);
   outline: none;
-  border-color: var(--control-btn-maximize-bg);
-  box-shadow: 0 0 0 2px rgba(76, 209, 55, 0.2);
 }
 
-.form-input.error {
-  border-color: var(--control-btn-close-bg);
+.setup-input.error {
+  border-color: #ff6b6b;
+  background: rgba(255, 107, 107, 0.2);
+  animation: shake 0.5s ease-in-out;
 }
 
-.error-message {
-  display: block;
-  font-size: 12px;
-  color: var(--control-btn-close-bg);
-  margin-top: 4px;
+@keyframes shake {
+  0%, 100% { transform: translateX(0); }
+  25% { transform: translateX(-10px); }
+  75% { transform: translateX(10px); }
 }
 
-.checkbox-label {
+.terms-section {
+  width: 100%;
+  margin: 8px 0;
+}
+
+.terms-label {
   display: flex;
   align-items: flex-start;
   cursor: pointer;
-  font-size: 14px;
-  color: var(--content-text-color);
+  font-size: 0.9rem;
+  color: rgba(255, 255, 255, 0.8);
   line-height: 1.4;
+  text-align: center;
+  justify-content: center;
 }
 
-.checkbox-input {
+.terms-checkbox {
   margin-right: 8px;
   margin-top: 2px;
   width: 16px;
@@ -438,58 +501,83 @@ const goHome = () => {
   flex-shrink: 0;
 }
 
-.checkbox-text {
+.terms-text {
   display: flex;
   flex-wrap: wrap;
   align-items: center;
+  justify-content: center;
 }
 
 .terms-link {
   background: none;
   border: none;
-  color: var(--control-btn-maximize-bg);
-  font-size: 14px;
+  color: rgba(255, 255, 255, 0.9);
+  font-size: 0.9rem;
   cursor: pointer;
   text-decoration: underline;
   margin-left: 4px;
 }
 
 .terms-link:hover {
-  opacity: 0.8;
+  color: white;
 }
 
-.auth-button {
+.error-messages {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  gap: 8px;
+  margin-top: 12px;
+  min-height: 20px;
+}
+
+.error-message {
+  font-size: 0.9rem;
+  color: #ff6b6b;
+  text-shadow: 0 1px 3px rgba(0, 0, 0, 0.5);
+  text-align: center;
+  white-space: nowrap;
+}
+
+.setup-button {
   width: 100%;
-  padding: 14px;
-  background: var(--control-btn-maximize-bg);
+  height: 50px;
+  padding: 14px 24px;
+  background: rgba(255, 255, 255, 0.2);
+  backdrop-filter: blur(20px);
+  border: 2px solid rgba(255, 255, 255, 0.3);
+  border-radius: 50px;
   color: white;
-  border: none;
-  border-radius: var(--rounded-button);
-  font-size: 16px;
-  font-weight: 600;
+  font-size: 1rem;
+  font-weight: 500;
   cursor: pointer;
   transition: all 0.3s ease;
   display: flex;
   align-items: center;
   justify-content: center;
   gap: 8px;
+  outline: none;
+  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
 }
 
-.auth-button:hover:not(:disabled) {
+.setup-button:hover:not(:disabled) {
+  background: rgba(255, 255, 255, 0.3);
+  border-color: rgba(255, 255, 255, 0.5);
   transform: translateY(-2px);
-  box-shadow: 0 6px 20px rgba(76, 209, 55, 0.4);
+  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.3);
 }
 
-.auth-button:disabled {
+.setup-button:disabled {
   opacity: 0.6;
   cursor: not-allowed;
+  transform: none;
 }
 
 .loading-spinner {
-  width: 16px;
-  height: 16px;
+  width: 20px;
+  height: 20px;
   border: 2px solid transparent;
-  border-top: 2px solid white;
+  border-top: 2px solid currentColor;
   border-radius: 50%;
   animation: spin 1s linear infinite;
 }
@@ -499,57 +587,203 @@ const goHome = () => {
   100% { transform: rotate(360deg); }
 }
 
-.auth-footer {
+.setup-footer {
   margin-top: 24px;
   text-align: center;
 }
 
-.auth-footer-text {
-  font-size: 14px;
-  color: var(--content-text-color);
-  opacity: 0.7;
+.footer-text {
+  font-size: 0.9rem;
+  color: rgba(255, 255, 255, 0.8);
+  text-shadow: 0 1px 3px rgba(0, 0, 0, 0.5);
 }
 
-.auth-link {
+.footer-link {
   background: none;
   border: none;
-  color: var(--control-btn-maximize-bg);
-  font-size: 14px;
+  color: rgba(255, 255, 255, 0.9);
+  font-size: 0.9rem;
   cursor: pointer;
   text-decoration: underline;
   margin-left: 4px;
 }
 
-.auth-link:hover {
-  opacity: 0.8;
+.footer-link:hover {
+  color: white;
+}
+
+.status-bar {
+  position: absolute;
+  top: 0;
+  left: 0;
+  right: 0;
+  height: 22px;
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  padding: 0 20px;
+  background: var(--taskbar-background);
+  backdrop-filter: blur(20px);
+  -webkit-backdrop-filter: blur(20px);
+  color: var(--taskbar-item-text-color);
+  font-size: 12px;
+  font-weight: 500;
+  z-index: 2;
+  border-bottom: 1px solid rgba(255, 255, 255, 0.1);
+}
+
+.status-left,
+.status-center,
+.status-right {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+}
+
+.language-switcher-wrapper {
+  position: relative;
+}
+
+.language-switcher {
+  background: none;
+  border: none;
+  color: var(--taskbar-item-text-color);
+  font-size: 12px;
+  font-weight: 500;
+  cursor: pointer;
+  padding: 0 4px;
+  width: 24px;
+  height: 22px;
+  text-align: center;
+  line-height: 22px;
+  display: flex;
+  align-items: center;
+  justify-content: center;
+}
+
+.language-menu {
+  position: absolute;
+  top: calc(100% + 4px);
+  right: 0;
+  width: 160px;
+  background-color: var(--start-menu-background);
+  border: 1px solid var(--start-menu-border-color);
+  border-radius: 8px;
+  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
+  padding: 4px;
+  z-index: 10001;
+}
+
+.language-menu ul {
+  list-style: none;
+  padding: 0;
+  margin: 0;
+}
+
+.language-menu li {
+  display: flex;
+  align-items: center;
+  padding: 4px 8px;
+  border-radius: 4px;
+  cursor: pointer;
+  transition: background-color 0.15s ease-in-out;
+}
+
+.language-menu li:hover {
+  background-color: var(--taskbar-item-background-hover);
+}
+
+.checkmark {
+  width: 16px;
+  text-align: center;
+  margin-right: 4px;
 }
 
 /* Responsive Design */
 @media (max-width: 768px) {
-  .auth-window {
-    width: 95%;
-    margin: 20px;
+  .setup-content {
+    padding: 60px 20px 20px;
   }
   
-  .window-content {
-    padding: 24px;
+  .setup-title {
+    font-size: 2rem;
   }
   
-  .auth-title {
-    font-size: 24px;
+  .setup-subtitle {
+    font-size: 1rem;
+  }
+  
+  .setup-icon {
+    font-size: 3rem;
+  }
+  
+  .setup-input {
+    height: 44px;
+    padding: 12px 20px;
+    font-size: 0.9rem;
+  }
+  
+  .setup-button {
+    height: 44px;
+    font-size: 0.9rem;
+  }
+  
+  .status-bar {
+    padding: 8px 16px;
+    font-size: 0.8rem;
   }
 }
 
-/* Dark/Light theme transitions */
-.auth-page {
-  transition: background-color 0.3s ease;
+@media (max-width: 480px) {
+  .setup-content {
+    padding: 40px 16px 16px;
+  }
+  
+  .setup-title {
+    font-size: 1.8rem;
+  }
+  
+  .setup-subtitle {
+    font-size: 0.9rem;
+  }
+  
+  .setup-icon {
+    font-size: 2.5rem;
+  }
+  
+  .setup-input {
+    height: 40px;
+    padding: 10px 16px;
+    font-size: 0.85rem;
+  }
+  
+  .setup-button {
+    height: 40px;
+    font-size: 0.85rem;
+  }
+  
+  .terms-label {
+    font-size: 0.8rem;
+  }
+  
+  .footer-text {
+    font-size: 0.8rem;
+  }
 }
 
-.auth-window {
-  transition: background-color 0.3s ease, border-color 0.3s ease;
-}
-
-.window-content {
-  transition: color 0.3s ease;
+/* Dark mode adjustments */
+@media (prefers-color-scheme: dark) {
+  .background-image {
+    background: linear-gradient(135deg, 
+      #1e293b 0%, 
+      #334155 25%, 
+      #475569 50%, 
+      #64748b 75%, 
+      #94a3b8 100%);
+  }
+  
+  .glass-layer {
+    background: rgba(0, 0, 0, 0.1);
+  }
 }
 </style>