diff --git a/.eslintcache b/.eslintcache
index 07a89d0..af22109 100644
--- a/.eslintcache
+++ b/.eslintcache
@@ -1 +1 @@
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\ No newline at end of file
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\ No newline at end of file
diff --git a/src/App.js b/src/App.js
index c584eef..399506c 100644
--- a/src/App.js
+++ b/src/App.js
@@ -1,28 +1,42 @@
 import './App.css';
 import React from 'react';
-import CommentList from './components/CommentList';
-import CommentBox2 from './components/CommentBox2';
-
+import ThemeContext from './theme-context';
+import ThemedBar from './components/ThemedBar';
+const themes = {
+  light: {
+    className: 'btn btn-primary',
+    bgColor: '#eeeeee',
+    color: '#000'
+  },
+  dark: {
+    className: 'btn btn-light',
+    bgColor: '#222222',
+    color: '#fff'
+  }
+}
 class App extends React.Component {
   constructor(props) {
     super(props);
     this.state = {
-      comments: ['this is my first line']
+      theme: 'light'
     }
-    this.add = this.add.bind(this);
+    this.changeTheme = this.changeTheme.bind(this);
   }
-  add(comment) {
+  changeTheme(text){
+    //console.log(text);
     this.setState({
-      comments: [...this.state.comments, comment]
+      theme: text
     });
   }
   render() {
-    const { comments } = this.state;
     return (
-      <div>
-        <CommentList comments={comments} />
-        <CommentBox2 onAdd={this.add} count={comments.length} />
-      </div>
+      <ThemeContext.Provider value={themes[this.state.theme]}>
+        <div className="App">
+          <a href="#theme-switcher" className="btn btn-light" onClick={() => {this.changeTheme('light')}}>浅色主题</a>
+          <a href="#theme-switcher" className="btn btn-secondary" onClick={() => {this.changeTheme('dark')}}>深色主题</a>
+          <ThemedBar />
+        </div>
+      </ThemeContext.Provider>
     )
   }
 }
diff --git a/src/components/ThemedBar.js b/src/components/ThemedBar.js
new file mode 100755
index 0000000..25b71a3
--- /dev/null
+++ b/src/components/ThemedBar.js
@@ -0,0 +1,29 @@
+import React from 'react';
+import ThemeContext from '../theme-context';
+
+class ThemedBar extends React.Component {
+
+    render() {
+        return (
+            <ThemeContext.Consumer>
+                {
+                    theme => {
+                        return (
+                            <div
+                                className="alert mt-5"
+                                style={
+                                    { backgroundColor: theme.bgColor, color: theme.color }
+                                }
+                            >
+                                样式区域
+                                <button className={theme.className}>样式按钮</button>
+                            </div>
+                        )
+                    }
+                }
+            </ThemeContext.Consumer>
+        )
+    }
+}
+
+export default ThemedBar;
\ No newline at end of file
diff --git a/src/theme-context.js b/src/theme-context.js
new file mode 100755
index 0000000..20ba28e
--- /dev/null
+++ b/src/theme-context.js
@@ -0,0 +1,5 @@
+import React from 'react';
+
+const ThemeContext = React.createContext();
+
+export default ThemeContext;
\ No newline at end of file