diff --git a/app/src/main/res/values-v31/colors.xml b/app/src/main/res/values-v31/colors.xml
index 8ceb0d38..982aed66 100644
--- a/app/src/main/res/values-v31/colors.xml
+++ b/app/src/main/res/values-v31/colors.xml
@@ -1,4 +1,5 @@
 <?xml version="1.0" encoding="utf-8"?>
+<!-- 暫定： AOSP Modsから借りています -->
 <resources>
     <!-- UI -->
     <color name="ui_bg">@android:color/system_neutral1_50</color>
diff --git a/app/src/main/res/values/colors.xml b/app/src/main/res/values/colors.xml
new file mode 100644
index 00000000..7dae7afe
--- /dev/null
+++ b/app/src/main/res/values/colors.xml
@@ -0,0 +1,61 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Github Copilot に生成してもらった適当な定義なので、リリースまでに修正してください -->
+<resources>
+    <!-- UI -->
+    <color name="ui_bg">#F5F5F5</color>
+    <color name="ui_fg">#212121</color>
+    <color name="ui_fg_disabled">#BDBDBD</color>
+    <color name="ui_fg_secondary">#757575</color>
+    <color name="ui_accent">#FF4081</color>
+    <color name="ui_accent_inverse">#FF80AB</color>
+    <color name="ui_accent_variant">#C60055</color>
+    <color name="ui_surface">#FFFFFF</color>
+    <color name="ui_primary_surface">#F5F5F5</color>
+    <color name="changelog_bg">#E0E0E0</color>
+    <color name="changelog_border">#BDBDBD</color>
+    <color name="error">#DA000E</color>
+    <color name="success">#008753</color>
+
+    <!-- Launcher icon -->
+    <color name="launcher_fg">#616161</color>
+    <color name="launcher_bg">#FFFFFF</color>
+
+    <color name="accent_light">#FF80AB</color>
+    <color name="accent_dark">#C60055</color>
+    <color name="accent_variant_light">#EA80FC</color>
+    <color name="accent_variant_dark">#AA00FF</color>
+
+    <!-- Material3 colors -->
+    <color name="colorPrimaryLight">#C5E1A5</color>
+    <color name="colorPrimaryDark">#33691E</color>
+    <color name="colorPrimaryContainerLight">#DCEDC8</color>
+    <color name="colorPrimaryContainerDark">#689F38</color>
+    <color name="colorOnPrimaryContainerLight">#F1F8E9</color>
+    <color name="colorOnPrimaryContainerDark">#827717</color>
+    <color name="colorSecondaryContainerLight">#FFECB3</color>
+    <color name="colorSecondaryContainerDark">#FFECB3</color>
+    <color name="colorOnSecondaryContainerLight">#FFF9C4</color>
+    <color name="colorOnSecondaryContainerDark">#FFF9C4</color>
+    <color name="colorTertiaryLight">#D1C4E9</color>
+    <color name="colorTertiaryDark">#4527A0</color>
+    <color name="colorOnTertiaryLight">#EDE7F6</color>
+    <color name="colorOnTertiaryDark">#311B92</color>
+    <color name="colorTertiaryContainerLight">#B39DDB</color>
+    <color name="colorTertiaryContainerDark">#512DA8</color>
+    <color name="colorOnTertiaryContainerLight">#673AB7</color>
+    <color name="colorOnTertiaryContainerDark">#B39DDB</color>
+    <color name="colorSurfaceLight">#FFFFFF</color>
+    <color name="colorSurfaceDark">#212121</color>
+    <color name="colorOnSurfaceLight">#212121</color>
+    <color name="colorOnSurfaceDark">#FFFFFF</color>
+    <color name="colorSurfaceVariantLight">#E0E0E0</color>
+    <color name="colorSurfaceVariantDark">#757575</color>
+    <color name="colorOnSurfaceVariantLight">#757575</color>
+    <color name="colorOnSurfaceVariantDark">#BDBDBD</color>
+    <color name="colorOutlineLight">#9E9E9E</color>
+    <color name="colorOutlineDark">#616161</color>
+    <color name="colorErrorContainerLight">#FFF9DEDC</color>
+    <color name="colorErrorContainerDark">#FF8C1D18</color>
+    <color name="colorOnErrorContainerLight">#FF410E0B</color>
+    <color name="colorOnErrorContainerDark">#FFF9DEDC</color>
+</resources>
\ No newline at end of file