diff --git a/.gitignore b/.gitignore
index 9014f1e..4a751a3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -9,3 +9,11 @@ coverage/
 neo-companion.sqlite
 apps/desktop/src-tauri/target/
 apps/desktop/src-tauri/gen/
+
+# Windows reserved device names that may accidentally materialize as files
+# (e.g. when a `> nul` redirection is run in a non-Win32 shell context).
+nul
+CON
+PRN
+AUX
+NUL
diff --git a/apps/desktop/src/assets/companion/companion-focus.png b/apps/desktop/src/assets/companion/companion-focus.png
new file mode 100644
index 0000000..3792abd
Binary files /dev/null and b/apps/desktop/src/assets/companion/companion-focus.png differ
diff --git a/apps/desktop/src/assets/companion/companion-full.png b/apps/desktop/src/assets/companion/companion-full.png
deleted file mode 100644
index 9ab7754..0000000
Binary files a/apps/desktop/src/assets/companion/companion-full.png and /dev/null differ
diff --git a/apps/desktop/src/assets/companion/companion-happy.png b/apps/desktop/src/assets/companion/companion-happy.png
new file mode 100644
index 0000000..8c9481b
Binary files /dev/null and b/apps/desktop/src/assets/companion/companion-happy.png differ
diff --git a/apps/desktop/src/assets/companion/companion-idle.png b/apps/desktop/src/assets/companion/companion-idle.png
new file mode 100644
index 0000000..d14006b
Binary files /dev/null and b/apps/desktop/src/assets/companion/companion-idle.png differ
diff --git a/apps/desktop/src/assets/companion/companion-sleepy.png b/apps/desktop/src/assets/companion/companion-sleepy.png
new file mode 100644
index 0000000..42f83e5
Binary files /dev/null and b/apps/desktop/src/assets/companion/companion-sleepy.png differ
diff --git a/apps/desktop/src/assets/companion/companion-thinking.png b/apps/desktop/src/assets/companion/companion-thinking.png
new file mode 100644
index 0000000..b730e44
Binary files /dev/null and b/apps/desktop/src/assets/companion/companion-thinking.png differ
diff --git a/apps/desktop/src/assets/companion/companion-warn.png b/apps/desktop/src/assets/companion/companion-warn.png
new file mode 100644
index 0000000..0b232d7
Binary files /dev/null and b/apps/desktop/src/assets/companion/companion-warn.png differ
diff --git a/apps/desktop/src/assets/companion/index.ts b/apps/desktop/src/assets/companion/index.ts
new file mode 100644
index 0000000..caeeb00
--- /dev/null
+++ b/apps/desktop/src/assets/companion/index.ts
@@ -0,0 +1,16 @@
+import type { CompanionState } from "@neo-companion/shared";
+import focus from "./companion-focus.png";
+import happy from "./companion-happy.png";
+import idle from "./companion-idle.png";
+import sleepy from "./companion-sleepy.png";
+import thinking from "./companion-thinking.png";
+import warn from "./companion-warn.png";
+
+export const companionStateImages: Record<CompanionState, string> = {
+  idle,
+  focus,
+  happy,
+  thinking,
+  warn,
+  sleepy,
+};
diff --git a/apps/desktop/src/components/panel/MiniPetAvatar.vue b/apps/desktop/src/components/panel/MiniPetAvatar.vue
index a5c00c1..27aeb36 100644
--- a/apps/desktop/src/components/panel/MiniPetAvatar.vue
+++ b/apps/desktop/src/components/panel/MiniPetAvatar.vue
@@ -1,11 +1,14 @@
 <script setup lang="ts">
+import type { CompanionState } from "@neo-companion/shared";
+import { companionStateImages } from "../../assets/companion";
+
 defineProps<{
-  state: string;
+  state: CompanionState;
 }>();
 </script>
 
 <template>
   <div class="mini-pet-avatar" :data-state="state">
-    <img src="../../assets/companion/companion-full.png" alt="" />
+    <img :src="companionStateImages[state]" alt="" />
   </div>
 </template>
diff --git a/apps/desktop/src/components/panel/TopNav.vue b/apps/desktop/src/components/panel/TopNav.vue
index 4b4ef6c..5999c66 100644
--- a/apps/desktop/src/components/panel/TopNav.vue
+++ b/apps/desktop/src/components/panel/TopNav.vue
@@ -1,8 +1,9 @@
 <script setup lang="ts">
 import type { CompanionState } from "@neo-companion/shared";
+import { companionStateImages } from "../../assets/companion";
 
 defineProps<{
-  petState: CompanionState; // TODO: Phase 2 — use for dynamic avatar state
+  petState: CompanionState;
   isDark: boolean;
 }>();
 
@@ -16,19 +17,11 @@ const emit = defineEmits<{
   <nav class="panel-topnav" data-tauri-drag-region>
     <!-- Pet avatar button -->
     <button
-      class="icon-btn"
+      class="icon-btn companion-avatar-button"
       type="button"
-      style="padding: 0; overflow: hidden"
-      :style="{
-        background: 'radial-gradient(circle at 30% 30%, #ffe0a3, #ffb347 55%, #c2410c 100%)',
-        boxShadow: '0 6px 20px rgba(255,140,40,.35), inset 0 1px 0 rgba(255,255,255,.6)',
-      }"
+      aria-label="NeoCompanion 当前状态"
     >
-      <span style="position: relative; width: 48px; height: 48px; display: block">
-        <span style="position: absolute; left: 14px; top: 18px; width: 4px; height: 6px; background: #3b1f0a; border-radius: 2px"></span>
-        <span style="position: absolute; right: 14px; top: 18px; width: 4px; height: 6px; background: #3b1f0a; border-radius: 2px"></span>
-        <span style="position: absolute; left: 50%; bottom: 14px; width: 14px; height: 5px; border: 2px solid #3b1f0a; border-top: 0; border-radius: 0 0 12px 12px; transform: translateX(-50%)"></span>
-      </span>
+      <img class="companion-avatar-image" :src="companionStateImages[petState]" alt="" />
     </button>
 
     <!-- Theme toggle + Settings -->
@@ -57,3 +50,21 @@ const emit = defineEmits<{
     </button>
   </nav>
 </template>
+
+<style scoped>
+.companion-avatar-button {
+  padding: 2px;
+  overflow: hidden;
+  background: radial-gradient(circle at 50% 58%, #fff1b8, #f6b24e 62%, #c95d1b 100%);
+  box-shadow:
+    0 6px 20px rgba(255, 140, 40, 0.35),
+    inset 0 1px 0 rgba(255, 255, 255, 0.6);
+}
+
+.companion-avatar-image {
+  display: block;
+  width: 44px;
+  height: 44px;
+  object-fit: contain;
+}
+</style>
diff --git a/apps/desktop/src/components/pet/PetStage.vue b/apps/desktop/src/components/pet/PetStage.vue
index e74f6bc..3ba8edb 100644
--- a/apps/desktop/src/components/pet/PetStage.vue
+++ b/apps/desktop/src/components/pet/PetStage.vue
@@ -1,6 +1,6 @@
 <script setup lang="ts">
 import type { CompanionState } from "@neo-companion/shared";
-import companionFull from "../../assets/companion/companion-full.png";
+import { companionStateImages } from "../../assets/companion";
 
 defineProps<{
   state: CompanionState;
@@ -16,6 +16,6 @@ const emit = defineEmits<{
   <button class="pet-stage" type="button" aria-label="打开 NeoCompanion 面板" @click="emit('click')" @contextmenu.prevent="emit('contextmenu', $event)">
     <span class="pet-ambient-glow" aria-hidden="true"></span>
     <span class="pet-aura"></span>
-    <img class="companion-image" :src="companionFull" alt="NeoCompanion 桌宠" />
+    <img class="companion-image" :src="companionStateImages[state]" alt="NeoCompanion 桌宠" />
   </button>
 </template>
diff --git a/apps/desktop/src/styles/pet.css b/apps/desktop/src/styles/pet.css
index 00f9245..3ff31b8 100644
--- a/apps/desktop/src/styles/pet.css
+++ b/apps/desktop/src/styles/pet.css
@@ -74,7 +74,7 @@
   z-index: 1;
   display: block;
   width: auto;
-  max-width: min(88%, 250px);
+  max-width: min(94%, 280px);
   max-height: 390px;
   object-fit: contain;
   object-position: center bottom;
@@ -302,7 +302,7 @@
 
 @media (max-width: 760px) {
   .companion-image {
-    max-width: min(86%, 230px);
+    max-width: min(94%, 280px);
   }
 }