diff --git a/example/common/lib/main.dart b/example/common/lib/main.dart
index 83e72e9..8eb963b 100644
--- a/example/common/lib/main.dart
+++ b/example/common/lib/main.dart
@@ -15,7 +15,7 @@ class App extends StatelessWidget {
     return builder((context) {
       final platformBrightness = MediaQuery.of(context).platformBrightness;
       final brightness = context.findAndTrust<Brightness>();
-      final theme = context.findAndTrust<ThemeData>();
+      final theme = context.findAndTrust<Theme>();
       return [
         'Platform brightness: ${platformBrightness.name}'.asText,
         'Theme brightness: ${brightness.name}'.asText,
@@ -24,19 +24,19 @@ class App extends StatelessWidget {
       ].asColumn;
     })
         .center
-        .theme(light: const ThemeData.light(), dark: const ThemeData.dark())
+        .theme(light: const Theme.light(), dark: const Theme.dark())
         .ensureDirection(context)
         .ensureMedia(context);
   }
 }
 
-class ThemeData with Theme {
-  const ThemeData.light({
+class Theme with ThemeMixin {
+  const Theme.light({
     this.background = MonoColors.snow,
     this.foreground = MonoColors.ink,
   });
 
-  const ThemeData.dark({
+  const Theme.dark({
     this.background = MonoColors.night,
     this.foreground = MonoColors.lunar,
   });
diff --git a/lib/src/theme.dart b/lib/src/theme.dart
index 1c61fb6..c02d0fa 100644
--- a/lib/src/theme.dart
+++ b/lib/src/theme.dart
@@ -4,13 +4,35 @@ import 'package:flutter/widgets.dart';
 import 'inherit.dart';
 import 'wrap.dart';
 
-mixin Theme {
-  /// Default background of the theme.
-  /// It's recommended to use a final parameter rather than a getter.
+/// All handled theme data should have basic properties defined in this mixin.
+///
+/// The [foreground] and [background] are elementary components of a theme,
+/// without such parameters, the theme will be useless.
+/// So that they are required.
+///
+/// It's recommended to use a final parameter rather than a getter.
+/// It is defined as a getter here because of the limit of Dart syntax.
+/// For example:
+///
+/// ```dart
+/// class Theme with ThemeMixin {
+///   const Theme({
+///     required this.background,
+///     required this.foreground,
+///   })
+///
+///   @override
+///   final Color background;
+///
+///   @override
+///   final Color foreground;
+/// }
+/// ```
+mixin ThemeMixin {
+  /// Default background of the theme, see [ThemeMixin].
   Color get background;
 
-  /// Default foreground, text and icon color, of the theme.
-  /// It's recommended to use a final parameter rather than a getter.
+  /// Default foreground, text and icon color, of the theme, see [ThemeMixin].
   Color get foreground;
 }
 
@@ -27,7 +49,7 @@ extension WrapTheme on Widget {
   /// [light] theme directly when there's no [dark] theme,
   /// because even if the [dark] theme is not provided,
   /// it might be modifier by its descendants.
-  Widget theme<T extends Theme>({
+  Widget theme<T extends ThemeMixin>({
     required T light,
     T? dark,
     ThemeMode mode = ThemeMode.system,
@@ -40,11 +62,11 @@ extension WrapTheme on Widget {
       );
 }
 
-/// Handle a [Theme] and the [ThemeMode],
+/// Handle a [ThemeMixin] and the [ThemeMode],
 /// and it will also provide the [Brightness] of current theme.
-/// And you can also modify current [Theme] and [ThemeMode] from
+/// And you can also modify current [ThemeMixin] and [ThemeMode] from
 /// its descendants in the widget tree via the context.
-class ThemeHandler<T extends Theme> extends StatefulWidget {
+class ThemeHandler<T extends ThemeMixin> extends StatefulWidget {
   const ThemeHandler({
     super.key,
     required this.light,
@@ -62,7 +84,7 @@ class ThemeHandler<T extends Theme> extends StatefulWidget {
   State<ThemeHandler<T>> createState() => _ThemeHandlerState<T>();
 }
 
-class _ThemeHandlerState<T extends Theme> extends State<ThemeHandler<T>> {
+class _ThemeHandlerState<T extends ThemeMixin> extends State<ThemeHandler<T>> {
   late T _light = widget.light;
   late T _dark = widget.dark;
   late ThemeMode _mode = widget.mode;
diff --git a/test/theme_test.dart b/test/theme_test.dart
index fd4f00b..5d1f232 100644
--- a/test/theme_test.dart
+++ b/test/theme_test.dart
@@ -108,7 +108,7 @@ void main() {
   });
 }
 
-class CustomizedTheme with Theme {
+class CustomizedTheme with ThemeMixin {
   const CustomizedTheme.light({
     this.background = MonoColors.snow,
     this.foreground = MonoColors.coal,