diff --git a/frontend/androidApp/src/main/AndroidManifest.xml b/frontend/androidApp/src/main/AndroidManifest.xml
index 8383cf3..386ff70 100644
--- a/frontend/androidApp/src/main/AndroidManifest.xml
+++ b/frontend/androidApp/src/main/AndroidManifest.xml
@@ -8,8 +8,10 @@
     <application
         android:name="dev.plexus.android.PlexusApplication"
         android:allowBackup="true"
+        android:icon="@mipmap/ic_launcher"
         android:label="@string/app_name"
         android:networkSecurityConfig="@xml/network_security_config"
+        android:roundIcon="@mipmap/ic_launcher_round"
         android:supportsRtl="true"
         android:theme="@style/Theme.App.Starting">
 
@@ -24,6 +26,14 @@
             </intent-filter>
         </activity>
 
+        <!-- FCM default notification icon -->
+        <meta-data
+            android:name="com.google.firebase.messaging.default_notification_icon"
+            android:resource="@drawable/ic_notification" />
+        <meta-data
+            android:name="com.google.firebase.messaging.default_notification_color"
+            android:resource="@color/ic_launcher_background" />
+
         <!-- FCM Service -->
         <service
             android:name="dev.plexus.android.fcm.FcmService"
diff --git a/frontend/androidApp/src/main/kotlin/dev/plexus/android/notifications/NotificationDisplayer.kt b/frontend/androidApp/src/main/kotlin/dev/plexus/android/notifications/NotificationDisplayer.kt
index 5aff5be..42bcb5b 100644
--- a/frontend/androidApp/src/main/kotlin/dev/plexus/android/notifications/NotificationDisplayer.kt
+++ b/frontend/androidApp/src/main/kotlin/dev/plexus/android/notifications/NotificationDisplayer.kt
@@ -7,6 +7,7 @@ import android.content.Intent
 import androidx.core.app.NotificationCompat
 import androidx.core.content.getSystemService
 import dev.plexus.app.MainActivity
+import dev.plexus.app.R
 
 /**
  * 通知表示ユーティリティ
@@ -50,7 +51,7 @@ object NotificationDisplayer {
                 .Builder(context, channelId)
                 .setContentTitle(title)
                 .setContentText(message)
-                .setSmallIcon(android.R.drawable.ic_dialog_info)
+                .setSmallIcon(R.drawable.ic_notification)
                 .setAutoCancel(true)
                 .setContentIntent(pendingIntent)
                 .setPriority(NotificationCompat.PRIORITY_DEFAULT)
diff --git a/frontend/androidApp/src/main/res/drawable-hdpi/ic_notification.webp b/frontend/androidApp/src/main/res/drawable-hdpi/ic_notification.webp
new file mode 100644
index 0000000..1a93dfe
Binary files /dev/null and b/frontend/androidApp/src/main/res/drawable-hdpi/ic_notification.webp differ
diff --git a/frontend/androidApp/src/main/res/drawable-mdpi/ic_notification.webp b/frontend/androidApp/src/main/res/drawable-mdpi/ic_notification.webp
new file mode 100644
index 0000000..26618ba
Binary files /dev/null and b/frontend/androidApp/src/main/res/drawable-mdpi/ic_notification.webp differ
diff --git a/frontend/androidApp/src/main/res/drawable-xhdpi/ic_notification.webp b/frontend/androidApp/src/main/res/drawable-xhdpi/ic_notification.webp
new file mode 100644
index 0000000..bd2ca7b
Binary files /dev/null and b/frontend/androidApp/src/main/res/drawable-xhdpi/ic_notification.webp differ
diff --git a/frontend/androidApp/src/main/res/drawable-xxhdpi/ic_notification.webp b/frontend/androidApp/src/main/res/drawable-xxhdpi/ic_notification.webp
new file mode 100644
index 0000000..27f7f82
Binary files /dev/null and b/frontend/androidApp/src/main/res/drawable-xxhdpi/ic_notification.webp differ
diff --git a/frontend/androidApp/src/main/res/drawable-xxxhdpi/ic_notification.webp b/frontend/androidApp/src/main/res/drawable-xxxhdpi/ic_notification.webp
new file mode 100644
index 0000000..69fa8af
Binary files /dev/null and b/frontend/androidApp/src/main/res/drawable-xxxhdpi/ic_notification.webp differ
diff --git a/frontend/androidApp/src/main/res/drawable/ic_notification.xml b/frontend/androidApp/src/main/res/drawable/ic_notification.xml
deleted file mode 100644
index a94a890..0000000
--- a/frontend/androidApp/src/main/res/drawable/ic_notification.xml
+++ /dev/null
@@ -1,9 +0,0 @@
-<vector xmlns:android="http://schemas.android.com/apk/res/android"
-    android:width="24dp"
-    android:height="24dp"
-    android:viewportWidth="24"
-    android:viewportHeight="24">
-    <path
-        android:fillColor="#FFFFFF"
-        android:pathData="M12,2C6.48,2 2,6.48 2,12s4.48,10 2,12 2,17.52 6.48,19 12,22 10,22 17.52,10 17.52,6 12,19 6.48,19 19,12 19,6.48 6.48,10 10,6.48 17.52 17.52,10 17.52,6.48 17.52,12 19,12 19,6.48 19,6.48 10 10,6.48 17.52 17.52,17.52 10 17.52,12 19,12 19,12 19,6.48 19,6.48 10 10,6.48 17.52 17.52,12 12,17.52 6.48,19 12,19 19,6.48 19,6.48 10 10,6.48 17.52 17.52,6.48 12 12,6.48 17.52,17.52 6.48,19 12,19 19,6.48z"/>
-</vector>
diff --git a/frontend/androidApp/src/main/res/mipmap-anydpi-v26/ic_launcher.xml b/frontend/androidApp/src/main/res/mipmap-anydpi-v26/ic_launcher.xml
new file mode 100644
index 0000000..be43858
--- /dev/null
+++ b/frontend/androidApp/src/main/res/mipmap-anydpi-v26/ic_launcher.xml
@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@color/ic_launcher_background" />
+    <foreground android:drawable="@mipmap/ic_launcher_foreground" />
+</adaptive-icon>
diff --git a/frontend/androidApp/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml b/frontend/androidApp/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml
new file mode 100644
index 0000000..be43858
--- /dev/null
+++ b/frontend/androidApp/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml
@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
+    <background android:drawable="@color/ic_launcher_background" />
+    <foreground android:drawable="@mipmap/ic_launcher_foreground" />
+</adaptive-icon>
diff --git a/frontend/androidApp/src/main/res/mipmap-hdpi/ic_launcher.webp b/frontend/androidApp/src/main/res/mipmap-hdpi/ic_launcher.webp
new file mode 100644
index 0000000..cdf0d77
Binary files /dev/null and b/frontend/androidApp/src/main/res/mipmap-hdpi/ic_launcher.webp differ
diff --git a/frontend/androidApp/src/main/res/mipmap-hdpi/ic_launcher_foreground.webp b/frontend/androidApp/src/main/res/mipmap-hdpi/ic_launcher_foreground.webp
new file mode 100644
index 0000000..b8b4831
Binary files /dev/null and b/frontend/androidApp/src/main/res/mipmap-hdpi/ic_launcher_foreground.webp differ
diff --git a/frontend/androidApp/src/main/res/mipmap-mdpi/ic_launcher.webp b/frontend/androidApp/src/main/res/mipmap-mdpi/ic_launcher.webp
new file mode 100644
index 0000000..f540f73
Binary files /dev/null and b/frontend/androidApp/src/main/res/mipmap-mdpi/ic_launcher.webp differ
diff --git a/frontend/androidApp/src/main/res/mipmap-mdpi/ic_launcher_foreground.webp b/frontend/androidApp/src/main/res/mipmap-mdpi/ic_launcher_foreground.webp
new file mode 100644
index 0000000..b268add
Binary files /dev/null and b/frontend/androidApp/src/main/res/mipmap-mdpi/ic_launcher_foreground.webp differ
diff --git a/frontend/androidApp/src/main/res/mipmap-xhdpi/ic_launcher.webp b/frontend/androidApp/src/main/res/mipmap-xhdpi/ic_launcher.webp
new file mode 100644
index 0000000..1522c20
Binary files /dev/null and b/frontend/androidApp/src/main/res/mipmap-xhdpi/ic_launcher.webp differ
diff --git a/frontend/androidApp/src/main/res/mipmap-xhdpi/ic_launcher_foreground.webp b/frontend/androidApp/src/main/res/mipmap-xhdpi/ic_launcher_foreground.webp
new file mode 100644
index 0000000..4acba58
Binary files /dev/null and b/frontend/androidApp/src/main/res/mipmap-xhdpi/ic_launcher_foreground.webp differ
diff --git a/frontend/androidApp/src/main/res/mipmap-xxhdpi/ic_launcher.webp b/frontend/androidApp/src/main/res/mipmap-xxhdpi/ic_launcher.webp
new file mode 100644
index 0000000..5ce5d50
Binary files /dev/null and b/frontend/androidApp/src/main/res/mipmap-xxhdpi/ic_launcher.webp differ
diff --git a/frontend/androidApp/src/main/res/mipmap-xxhdpi/ic_launcher_foreground.webp b/frontend/androidApp/src/main/res/mipmap-xxhdpi/ic_launcher_foreground.webp
new file mode 100644
index 0000000..1398414
Binary files /dev/null and b/frontend/androidApp/src/main/res/mipmap-xxhdpi/ic_launcher_foreground.webp differ
diff --git a/frontend/androidApp/src/main/res/mipmap-xxxhdpi/ic_launcher.webp b/frontend/androidApp/src/main/res/mipmap-xxxhdpi/ic_launcher.webp
new file mode 100644
index 0000000..7074c2c
Binary files /dev/null and b/frontend/androidApp/src/main/res/mipmap-xxxhdpi/ic_launcher.webp differ
diff --git a/frontend/androidApp/src/main/res/mipmap-xxxhdpi/ic_launcher_foreground.webp b/frontend/androidApp/src/main/res/mipmap-xxxhdpi/ic_launcher_foreground.webp
new file mode 100644
index 0000000..5513a1b
Binary files /dev/null and b/frontend/androidApp/src/main/res/mipmap-xxxhdpi/ic_launcher_foreground.webp differ
diff --git a/frontend/androidApp/src/main/res/values/colors.xml b/frontend/androidApp/src/main/res/values/colors.xml
new file mode 100644
index 0000000..c5519e0
--- /dev/null
+++ b/frontend/androidApp/src/main/res/values/colors.xml
@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <color name="ic_launcher_background">#222D32</color>
+</resources>
diff --git a/frontend/shared/src/commonMain/kotlin/dev/plexus/shared/core/ui/theme/DesignTokens.kt b/frontend/shared/src/commonMain/kotlin/dev/plexus/shared/core/ui/theme/DesignTokens.kt
index e0e84a6..82b9dd0 100644
--- a/frontend/shared/src/commonMain/kotlin/dev/plexus/shared/core/ui/theme/DesignTokens.kt
+++ b/frontend/shared/src/commonMain/kotlin/dev/plexus/shared/core/ui/theme/DesignTokens.kt
@@ -59,7 +59,7 @@ data class PlexusShapes(
 
 @Immutable
 data class PlexusExtendedColors(
-    val success: Color = Color(0xFF4CAF50), // 接続成功、正常状態（緑）
+    val success: Color = Teal400, // 接続成功、正常状態
 )
 
 internal val LocalPlexusDimens = staticCompositionLocalOf { PlexusDimens() }
diff --git a/frontend/shared/src/commonMain/kotlin/dev/plexus/shared/core/ui/theme/Theme.kt b/frontend/shared/src/commonMain/kotlin/dev/plexus/shared/core/ui/theme/Theme.kt
index 4ea7658..28a056c 100644
--- a/frontend/shared/src/commonMain/kotlin/dev/plexus/shared/core/ui/theme/Theme.kt
+++ b/frontend/shared/src/commonMain/kotlin/dev/plexus/shared/core/ui/theme/Theme.kt
@@ -21,18 +21,18 @@ val Zinc800 = Color(0xFF27272A)
 val Zinc900 = Color(0xFF18181B)
 val Zinc950 = Color(0xFF09090B)
 
-// Cyan Palette（ブランドカラー）
-val Cyan50 = Color(0xFFECFEFF)
-val Cyan100 = Color(0xFFCFFAFE)
-val Cyan200 = Color(0xFFA5F3FC)
-val Cyan300 = Color(0xFF67E8F9)
-val Cyan400 = Color(0xFF22D3EE)
-val Cyan500 = Color(0xFF06B6D4)
-val Cyan600 = Color(0xFF0891B2)
-val Cyan700 = Color(0xFF0E7490)
-val Cyan800 = Color(0xFF155E75)
-val Cyan900 = Color(0xFF164E63)
-val Cyan950 = Color(0xFF083344)
+// Teal Palette（ブランドカラー）
+val Teal50 = Color(0xFFF0FDFA)
+val Teal100 = Color(0xFFCCFBF1)
+val Teal200 = Color(0xFF99F6E4)
+val Teal300 = Color(0xFF5EEAD4)
+val Teal400 = Color(0xFF2DD4BF)
+val Teal500 = Color(0xFF14B8A6)
+val Teal600 = Color(0xFF0D9488)
+val Teal700 = Color(0xFF0F766E)
+val Teal800 = Color(0xFF115E59)
+val Teal900 = Color(0xFF134E4A)
+val Teal950 = Color(0xFF042F2E)
 
 // === Error Colors ===
 // Light Theme
@@ -49,16 +49,16 @@ private val OnErrorContainerRedDark = ErrorContainerRed
 
 private val LightColorScheme =
     lightColorScheme(
-        // === Primary: Cyan ===
-        primary = Cyan600,
+        // === Primary: Teal ===
+        primary = Teal600,
         onPrimary = Color.White,
-        primaryContainer = Cyan100,
-        onPrimaryContainer = Cyan950,
-        // === Secondary: Cyan ===
-        secondary = Cyan500,
+        primaryContainer = Teal100,
+        onPrimaryContainer = Teal950,
+        // === Secondary: Teal ===
+        secondary = Teal500,
         onSecondary = Color.White,
-        secondaryContainer = Cyan300,
-        onSecondaryContainer = Cyan950,
+        secondaryContainer = Teal300,
+        onSecondaryContainer = Teal950,
         // === Tertiary: Zinc ===
         tertiary = Zinc700,
         onTertiary = Zinc50,
@@ -87,18 +87,19 @@ private val LightColorScheme =
         outlineVariant = Zinc200,
     )
 
+// Pattern A: primary = Teal300 (#5EEAD4)
 private val DarkColorScheme =
     darkColorScheme(
-        // === Primary: Cyan ===
-        primary = Cyan500,
-        onPrimary = Cyan50,
-        primaryContainer = Cyan700,
-        onPrimaryContainer = Cyan50,
-        // === Secondary: Cyan ===
-        secondary = Cyan400,
-        onSecondary = Cyan950,
-        secondaryContainer = Cyan600,
-        onSecondaryContainer = Cyan100,
+        // === Primary: Teal ===
+        primary = Teal300,
+        onPrimary = Teal950,
+        primaryContainer = Teal700,
+        onPrimaryContainer = Teal50,
+        // === Secondary: Teal ===
+        secondary = Teal400,
+        onSecondary = Teal950,
+        secondaryContainer = Teal600,
+        onSecondaryContainer = Teal100,
         // === Tertiary: Zinc ===
         tertiary = Zinc300,
         onTertiary = Zinc900,