diff --git a/frontend/src/components/layout/AppHeader.vue b/frontend/src/components/layout/AppHeader.vue
index e432879e..5593c8bb 100644
--- a/frontend/src/components/layout/AppHeader.vue
+++ b/frontend/src/components/layout/AppHeader.vue
@@ -207,7 +207,7 @@ const pageDescription = computed(() => {
 });
 
 function toggleMobileSidebar() {
-  appStore.toggleSidebar();
+  appStore.toggleMobileSidebar();
 }
 
 function toggleDropdown() {
diff --git a/frontend/src/components/layout/AppSidebar.vue b/frontend/src/components/layout/AppSidebar.vue
index 3ae63abe..7d5cf341 100644
--- a/frontend/src/components/layout/AppSidebar.vue
+++ b/frontend/src/components/layout/AppSidebar.vue
@@ -36,6 +36,7 @@
             class="sidebar-link mb-1"
             :class="{ 'sidebar-link-active': isActive(item.path) }"
             :title="sidebarCollapsed ? item.label : undefined"
+            @click="handleMenuItemClick"
           >
             <component :is="item.icon" class="w-5 h-5 flex-shrink-0" />
             <transition name="fade">
@@ -58,6 +59,7 @@
             class="sidebar-link mb-1"
             :class="{ 'sidebar-link-active': isActive(item.path) }"
             :title="sidebarCollapsed ? item.label : undefined"
+            @click="handleMenuItemClick"
           >
             <component :is="item.icon" class="w-5 h-5 flex-shrink-0" />
             <transition name="fade">
@@ -77,6 +79,7 @@
             class="sidebar-link mb-1"
             :class="{ 'sidebar-link-active': isActive(item.path) }"
             :title="sidebarCollapsed ? item.label : undefined"
+            @click="handleMenuItemClick"
           >
             <component :is="item.icon" class="w-5 h-5 flex-shrink-0" />
             <transition name="fade">
@@ -142,9 +145,9 @@ const appStore = useAppStore();
 const authStore = useAuthStore();
 
 const sidebarCollapsed = computed(() => appStore.sidebarCollapsed);
+const mobileOpen = computed(() => appStore.mobileOpen);
 const isAdmin = computed(() => authStore.isAdmin);
 const isDark = ref(document.documentElement.classList.contains('dark'));
-const mobileOpen = ref(false);
 
 // Site settings
 const siteName = ref('Sub2API');
@@ -303,7 +306,15 @@ function toggleTheme() {
 }
 
 function closeMobile() {
-  mobileOpen.value = false;
+  appStore.setMobileOpen(false);
+}
+
+function handleMenuItemClick() {
+  if (mobileOpen.value) {
+    setTimeout(() => {
+      appStore.setMobileOpen(false);
+    }, 150);
+  }
 }
 
 function isActive(path: string): boolean {
diff --git a/frontend/src/stores/app.ts b/frontend/src/stores/app.ts
index 4313cb82..1bf1a6f3 100644
--- a/frontend/src/stores/app.ts
+++ b/frontend/src/stores/app.ts
@@ -12,6 +12,7 @@ export const useAppStore = defineStore('app', () => {
   // ==================== State ====================
 
   const sidebarCollapsed = ref<boolean>(false);
+  const mobileOpen = ref<boolean>(false);
   const loading = ref<boolean>(false);
   const toasts = ref<Toast[]>([]);
 
@@ -50,6 +51,21 @@ export const useAppStore = defineStore('app', () => {
     sidebarCollapsed.value = collapsed;
   }
 
+  /**
+   * Toggle mobile sidebar open state
+   */
+  function toggleMobileSidebar(): void {
+    mobileOpen.value = !mobileOpen.value;
+  }
+
+  /**
+   * Set mobile sidebar open state explicitly
+   * @param open - Whether mobile sidebar should be open
+   */
+  function setMobileOpen(open: boolean): void {
+    mobileOpen.value = open;
+  }
+
   /**
    * Set global loading state
    * @param isLoading - Whether app is in loading state
@@ -257,6 +273,7 @@ export const useAppStore = defineStore('app', () => {
   return {
     // State
     sidebarCollapsed,
+    mobileOpen,
     loading,
     toasts,
 
@@ -275,6 +292,8 @@ export const useAppStore = defineStore('app', () => {
     // Actions
     toggleSidebar,
     setSidebarCollapsed,
+    toggleMobileSidebar,
+    setMobileOpen,
     setLoading,
     showToast,
     showSuccess,
diff --git a/frontend/src/views/admin/UsageView.vue b/frontend/src/views/admin/UsageView.vue
index 7c3f98aa..d0aec771 100644
--- a/frontend/src/views/admin/UsageView.vue
+++ b/frontend/src/views/admin/UsageView.vue
@@ -43,13 +43,12 @@
                 <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M12 8c-1.657 0-3 .895-3 2s1.343 2 3 2 3 .895 3 2-1.343 2-3 2m0-8c1.11 0 2.08.402 2.599 1M12 8V7m0 1v8m0 0v1m0-1c-1.11 0-2.08-.402-2.599-1M21 12a9 9 0 11-18 0 9 9 0 0118 0z" />
               </svg>
             </div>
-            <div>
+            <div class="min-w-0 flex-1">
               <p class="text-xs font-medium text-gray-500 dark:text-gray-400">{{ t('usage.totalCost') }}</p>
-              <div class="flex items-baseline gap-2">
-                <p class="text-xl font-bold text-green-600 dark:text-green-400">${{ (usageStats?.total_actual_cost || 0).toFixed(4) }}</p>
-                <span class="text-xs text-gray-400 dark:text-gray-500 line-through">${{ (usageStats?.total_cost || 0).toFixed(4) }}</span>
-              </div>
-              <p class="text-xs text-gray-500 dark:text-gray-400">{{ t('usage.actualCost') }} / {{ t('usage.standardCost') }}</p>
+              <p class="text-xl font-bold text-green-600 dark:text-green-400">${{ (usageStats?.total_actual_cost || 0).toFixed(4) }}</p>
+              <p class="text-xs text-gray-500 dark:text-gray-400">
+                {{ t('usage.actualCost') }} / <span class="line-through">${{ (usageStats?.total_cost || 0).toFixed(4) }}</span> {{ t('usage.standardCost') }}
+              </p>
             </div>
           </div>
         </div>
diff --git a/frontend/src/views/user/UsageView.vue b/frontend/src/views/user/UsageView.vue
index c81f4c87..eda1f021 100644
--- a/frontend/src/views/user/UsageView.vue
+++ b/frontend/src/views/user/UsageView.vue
@@ -43,13 +43,12 @@
                 <path stroke-linecap="round" stroke-linejoin="round" stroke-width="2" d="M12 8c-1.657 0-3 .895-3 2s1.343 2 3 2 3 .895 3 2-1.343 2-3 2m0-8c1.11 0 2.08.402 2.599 1M12 8V7m0 1v8m0 0v1m0-1c-1.11 0-2.08-.402-2.599-1M21 12a9 9 0 11-18 0 9 9 0 0118 0z" />
               </svg>
             </div>
-            <div>
+            <div class="min-w-0 flex-1">
               <p class="text-xs font-medium text-gray-500 dark:text-gray-400">{{ t('usage.totalCost') }}</p>
-              <div class="flex items-baseline gap-2">
-                <p class="text-xl font-bold text-green-600 dark:text-green-400">${{ (usageStats?.total_actual_cost || 0).toFixed(4) }}</p>
-                <span class="text-xs text-gray-400 dark:text-gray-500 line-through">${{ (usageStats?.total_cost || 0).toFixed(4) }}</span>
-              </div>
-              <p class="text-xs text-gray-500 dark:text-gray-400">{{ t('usage.actualCost') }} / {{ t('usage.standardCost') }}</p>
+              <p class="text-xl font-bold text-green-600 dark:text-green-400">${{ (usageStats?.total_actual_cost || 0).toFixed(4) }}</p>
+              <p class="text-xs text-gray-500 dark:text-gray-400">
+                {{ t('usage.actualCost') }} / <span class="line-through">${{ (usageStats?.total_cost || 0).toFixed(4) }}</span> {{ t('usage.standardCost') }}
+              </p>
             </div>
           </div>
         </div>