diff --git a/src/App.vue b/src/App.vue
index 9be723c..5950714 100644
--- a/src/App.vue
+++ b/src/App.vue
@@ -1,9 +1,11 @@
 <script setup lang="ts">
 import { useAuthStore } from '@/stores/auth'
 import { useRouter } from 'vue-router'
+import { useTheme } from '@/composables/useTheme'
 
 const auth = useAuthStore()
 const router = useRouter()
+const theme = useTheme()
 
 async function handleLogout() {
   try {
@@ -27,9 +29,19 @@ async function handleLogout() {
         <a v-if="auth.isLoggedIn" href="#" @click.prevent="handleLogout">退出</a>
         <router-link v-else to="/login">登录</router-link>
       </nav>
+      <button
+        class="theme-toggle"
+        type="button"
+        :title="theme.isDark ? '切至天青昼' : '切至黛墨夜'"
+        @click="theme.toggle()"
+      >{{ theme.isDark ? '昼' : '夜' }}</button>
     </header>
     <main class="app-main">
-      <router-view />
+      <router-view v-slot="{ Component }">
+        <transition name="page" mode="out-in">
+          <component :is="Component" />
+        </transition>
+      </router-view>
     </main>
   </div>
 </template>
@@ -39,42 +51,85 @@ async function handleLogout() {
   box-sizing: border-box;
 }
 
-body {
-  margin: 0;
-  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'PingFang SC',
-    'Microsoft YaHei', sans-serif;
-  background-color: #f5f6f8;
-  color: #24292f;
-  line-height: 1.6;
-}
-
 .app-header {
   display: flex;
   align-items: center;
-  justify-content: space-between;
+  gap: 20px;
   padding: 0 24px;
-  height: 56px;
-  background-color: #1f2430;
-  color: #fff;
+  height: 60px;
+  background-color: var(--ac-header-bg);
+  color: var(--ac-header-text);
+  border-bottom: 1px solid var(--ac-border);
+  transition: background-color var(--song-dur-2) var(--song-ease), color var(--song-dur-2) var(--song-ease);
 }
 
 .app-header .brand {
-  color: #fff;
+  display: flex;
+  align-items: center;
+  height: 100%;
+  margin-right: auto;
+  color: var(--ac-header-text);
+  font-family: var(--song-font-display);
   font-size: 18px;
-  font-weight: 700;
+  font-weight: 400;
+  letter-spacing: 0.06em;
   text-decoration: none;
 }
 
+.nav-links {
+  display: flex;
+  align-items: center;
+  height: 100%;
+  gap: 6px;
+}
+
 .nav-links a,
 .nav-links .username {
-  margin-left: 18px;
-  color: #cfd3dc;
+  color: var(--ac-header-muted);
   text-decoration: none;
   font-size: 14px;
 }
 
+.nav-links a {
+  display: inline-flex;
+  align-items: center;
+  height: 100%;
+  padding: 0 12px;
+  color: var(--ac-header-muted);
+}
+
 .nav-links a:hover {
-  color: #fff;
+  color: var(--ac-header-text);
+}
+
+.nav-links a.router-link-active {
+  color: var(--ac-header-text);
+  background: var(--ac-header-active-bg);
+}
+
+.nav-links .username {
+  margin-left: 12px;
+}
+
+.theme-toggle {
+  width: 34px;
+  height: 34px;
+  flex-shrink: 0;
+  border: 1px solid var(--ac-border);
+  border-radius: var(--ac-radius-m);
+  background: transparent;
+  color: var(--ac-header-muted);
+  font-family: var(--song-font-serif);
+  font-size: 15px;
+  letter-spacing: 0.1em;
+  cursor: pointer;
+  transition: color var(--song-dur-1) var(--song-ease), border-color var(--song-dur-1) var(--song-ease), background var(--song-dur-1) var(--song-ease);
+}
+
+.theme-toggle:hover {
+  color: var(--ac-header-text);
+  border-color: var(--ac-header-muted);
+  background: var(--ac-header-active-bg);
 }
 
 .app-main {
diff --git a/src/views/ArticleDetailView.vue b/src/views/ArticleDetailView.vue
index bc37b54..5c0a1f5 100644
--- a/src/views/ArticleDetailView.vue
+++ b/src/views/ArticleDetailView.vue
@@ -72,26 +72,29 @@ watch(slug, load, { immediate: true })
 
 <style scoped>
 .article {
-  background: #fff;
-  border: 1px solid #e5e5ea;
-  border-radius: 8px;
+  background: var(--ac-bg-card);
+  border: 1px solid var(--ac-border);
+  border-radius: var(--song-radius-l);
   padding: 24px;
 }
 
 .detail-title {
+  font-family: var(--song-font-display);
+  font-weight: 400;
+  letter-spacing: 0.02em;
   margin: 0 0 12px;
   font-size: 26px;
 }
 
 .detail-summary {
-  color: #5c6470;
+  color: var(--ac-text-secondary);
   font-size: 15px;
 }
 
 .detail-meta {
   display: flex;
   gap: 20px;
-  color: #8a93a3;
+  color: var(--ac-text-disabled);
   font-size: 13px;
   margin: 12px 0;
 }
@@ -104,23 +107,23 @@ watch(slug, load, { immediate: true })
   display: inline-block;
   margin-right: 8px;
   padding: 2px 10px;
-  background: #eef3ff;
-  color: #3b5bdb;
-  border-radius: 12px;
+  background: var(--ac-primary-bg);
+  color: var(--ac-primary-strong);
+  border-radius: var(--song-radius-m);
   font-size: 12px;
 }
 
 .article-content {
-  border-top: 1px solid #eee;
+  border-top: 1px solid var(--ac-border);
   padding-top: 20px;
   word-break: break-word;
 }
 
 .hint-text {
-  color: #8a93a3;
+  color: var(--ac-text-disabled);
 }
 
 .error-text {
-  color: #d33c3c;
+  color: var(--ac-danger);
 }
 </style>
\ No newline at end of file
diff --git a/src/views/HomeView.vue b/src/views/HomeView.vue
index 8d9ee81..e9a2c53 100644
--- a/src/views/HomeView.vue
+++ b/src/views/HomeView.vue
@@ -77,15 +77,18 @@ onMounted(load)
 }
 
 .page-title {
+  font-family: var(--song-font-display);
   font-size: 24px;
+  font-weight: 400;
+  letter-spacing: 0.04em;
   margin: 0 0 20px;
 }
 
 .error-text {
-  color: #d33c3c;
+  color: var(--ac-danger);
 }
 
 .hint-text {
-  color: #8a93a3;
+  color: var(--ac-text-disabled);
 }
 </style>
\ No newline at end of file
diff --git a/src/views/NotFoundView.vue b/src/views/NotFoundView.vue
index f5cc3cb..b5587a0 100644
--- a/src/views/NotFoundView.vue
+++ b/src/views/NotFoundView.vue
@@ -18,17 +18,19 @@ setPageMeta({ title: '页面不存在' })
 }
 
 .not-found h1 {
-  font-size: 48px;
+  font-family: var(--song-font-display);
+  font-size: 72px;
+  font-weight: 400;
   margin: 0 0 12px;
 }
 
 .not-found p {
-  color: #5c6470;
+  color: var(--ac-text-secondary);
   margin: 0 0 20px;
 }
 
 .not-found a {
-  color: #3b82f6;
+  color: var(--ac-primary);
   text-decoration: none;
 }
 </style>
\ No newline at end of file
diff --git a/src/views/SearchView.vue b/src/views/SearchView.vue
index 420b8dc..13136ee 100644
--- a/src/views/SearchView.vue
+++ b/src/views/SearchView.vue
@@ -95,25 +95,38 @@ onMounted(() => {
 .search-input {
   flex: 1;
   padding: 10px 14px;
-  border: 1px solid #d3d8e0;
-  border-radius: 6px;
+  border: 1px solid var(--ac-input-border);
+  border-radius: var(--song-radius-l);
   font-size: 14px;
+  background: var(--ac-bg-card);
+  color: var(--ac-text);
+  transition: border-color var(--song-dur-1) var(--song-ease);
+}
+
+.search-input:focus {
+  border-color: var(--ac-primary);
+  outline: none;
 }
 
 .search-btn {
   padding: 10px 22px;
   border: none;
-  border-radius: 6px;
-  background: #3b82f6;
-  color: #fff;
+  border-radius: var(--song-radius-l);
+  background: var(--ac-primary-strong);
+  color: var(--ac-primary-text);
   cursor: pointer;
+  transition: opacity var(--song-dur-1) var(--song-ease);
+}
+
+.search-btn:hover {
+  opacity: 0.9;
 }
 
 .error-text {
-  color: #d33c3c;
+  color: var(--ac-danger);
 }
 
 .hint-text {
-  color: #8a93a3;
+  color: var(--ac-text-disabled);
 }
 </style>
\ No newline at end of file