diff --git a/backend/src/index.ts b/backend/src/index.ts
index af98f24..068cc71 100644
--- a/backend/src/index.ts
+++ b/backend/src/index.ts
@@ -42,6 +42,38 @@ app.use("/user", userRouter);
 app.use("/file", fileRouter);
 app.use("/email", emailRouter);
 
+// 要添加的新接口
+app.post("/sendMessage", async (req, res) => {
+  // 从 Hasura Action 的请求体中获取参数
+  const { user_uuid, room_uuid, content } = req.body.input;
+
+  // 输入验证
+  if (!content || content.trim() === "") {
+    return res.status(400).json({
+      message: "Content cannot be empty",
+    });
+  }
+
+  // 调用 Hasura GraphQL API 来插入数据
+  try {
+    const data = await sdk.addMessage({
+      user_uuid: user_uuid,
+      room_uuid: room_uuid,
+      content: content,
+    });
+
+    // 返回成功响应
+    return res.json({
+      uuid: data.insert_message_one?.uuid,
+    });
+  } catch (err) {
+    console.error(err);
+    return res.status(500).json({
+      message: "Failed to send message",
+    });
+  }
+});
+
 app.listen(port, () => {
   console.log(`Server running at ${address}:${port}/`);
 });
diff --git a/backend/src/user.ts b/backend/src/user.ts
index a93bd91..237b6a5 100644
--- a/backend/src/user.ts
+++ b/backend/src/user.ts
@@ -14,6 +14,15 @@ const router = express.Router();
 
 router.post("/login", async (req, res) => {
   const { username, password } = req.body;
+  if (username.length < 3 || username.length > 20) {
+    return res.status(400).json({
+      message: "Username must be between 3 and 20 characters",
+      extensions: {
+        code: "USER_INPUT_ERROR",
+        path: "$.args.username"
+      }
+    });
+  }
   if (!username || !password) {
     return res.status(422).send("422 Unprocessable Entity: Missing username or password");
   }
diff --git a/database/graphql/message.graphql b/database/graphql/message.graphql
index 994647c..3b24b6a 100644
--- a/database/graphql/message.graphql
+++ b/database/graphql/message.graphql
@@ -15,3 +15,14 @@ subscription getMessagesByRoom($room_uuid: uuid!) {
     created_at
   }
 }
+
+query getMessagesByUser($user_uuid: uuid!) {
+  message(where: {user_uuid: {_eq: $user_uuid}}, order_by: {created_at: desc}) {
+    uuid
+    content
+    created_at
+    room {
+      name
+    }
+  }
+}
diff --git a/database/graphql/room.graphql b/database/graphql/room.graphql
index 4f37de0..bc9cfb5 100644
--- a/database/graphql/room.graphql
+++ b/database/graphql/room.graphql
@@ -28,3 +28,14 @@ mutation joinRoom($user_uuid: uuid!, $room_uuid: uuid!) {
     room_uuid
   }
 }
+
+mutation quitRoom($user_uuid: uuid!, $room_uuid: uuid!) {
+  delete_user_room(
+    where: {user_uuid: {_eq: $user_uuid}, room_uuid: {_eq: $room_uuid}}
+  ) {
+    returning {
+      user_uuid
+      room_uuid
+    }
+  }
+}
diff --git a/database/graphql/user.graphql b/database/graphql/user.graphql
index d7780cd..3391efa 100644
--- a/database/graphql/user.graphql
+++ b/database/graphql/user.graphql
@@ -10,3 +10,13 @@ query getUsersByUsername($username: String!) {
     password
   }
 }
+
+mutation deleteUser($uuid: uuid!) {
+  delete_user(where: {uuid: {_eq: $uuid}}) {
+    returning {
+      uuid
+      username
+    }
+  }
+}
+
diff --git a/database/hasura/docker-compose.yaml b/database/hasura/docker-compose.yaml
new file mode 100644
index 0000000..39be6ca
--- /dev/null
+++ b/database/hasura/docker-compose.yaml
@@ -0,0 +1,24 @@
+version: "3.6"
+services:
+  postgres:
+    image: postgres:latest
+    container_name: postgres
+    restart: always
+    volumes:
+      - ~/data/postgres:/var/lib/postgresql/data
+    ports:
+      - "5432:5432"
+    environment:
+      POSTGRES_PASSWORD: postgrespassword
+  graphql-engine:
+    image: hasura/graphql-engine:latest
+    container_name: hasura
+    ports:
+      - "23333:8080"
+    depends_on:
+      - "postgres"
+    restart: always
+    environment:
+      HASURA_GRAPHQL_DATABASE_URL: postgres://postgres:postgrespassword@postgres:5432/postgres
+      HASURA_GRAPHQL_ENABLE_CONSOLE: "true"
+      HASURA_GRAPHQL_ENABLED_LOG_TYPES: startup, http-log, webhook-log, websocket-log, query-log
\ No newline at end of file
diff --git a/frontend/public/about-me.html b/frontend/public/about-me.html
new file mode 100644
index 0000000..36b6dfe
--- /dev/null
+++ b/frontend/public/about-me.html
@@ -0,0 +1,89 @@
+<!DOCTYPE html>
+<html lang="zh-CN">
+<head>
+  <meta charset="UTF-8">
+  <title>关于我</title>
+  <style>
+    body {
+      background-color: #f0f8ff;
+      color: #333;
+      font-family: Arial, sans-serif;
+      text-align: center;
+      padding: 20px;
+      transition: background .3s, color .3s;
+    }
+    h1 { color: #2c3e50; }
+    img { border-radius: 10px; margin-top: 20px; }
+    a { color: #1e90ff; text-decoration: none; }
+
+    body.dark {
+      background-color: #121212 !important;
+      color: #e0e0e0 !important;
+    }
+    body.dark a { color: #81c784; }
+    body.dark img { filter: brightness(.8) contrast(1.2); }
+
+    #toggleBtn {
+      position: fixed;
+      top: 20px;
+      right: 20px;
+      z-index: 9999;
+      padding: 6px 12px;
+      font-size: 14px;
+      cursor: pointer;
+    }
+  </style>
+</head>
+<body>
+  <h1>关于我</h1>
+  <p>你好！我叫<strong>懒人</strong>，是电子系一名学生。</p>
+
+  <h2>我的爱好</h2>
+  <ul>
+    <li>睡懒觉！</li>
+    <li>睡懒觉！</li>
+    <li>睡懒觉！</li>
+  </ul>
+
+  <h2>一件趣事</h2>
+  <p>前天有个会要开，完全忘记了！</p>
+
+  <h2>个人照片</h2>
+  <img src="https://i.ibb.co/1tvkMhX5/c5b601e47c27c660243aeb20b2ee8b26.png" alt="我的照片">
+
+  <p>想回首页？<a href="index.html">点这里</a></p>
+
+  <button id="toggleBtn">🌓 切换暗色模式</button>
+  <section id="githubSec">
+    <h2>GitHub 实时数据</h2>
+    <p>加载中…</p>
+  </section>
+
+  <script>
+    const toggleBtn = document.getElementById('toggleBtn');
+    toggleBtn.addEventListener('click', () => {
+      document.body.classList.toggle('dark');
+      toggleBtn.textContent = document.body.classList.contains('dark')
+        ? '☀️ 亮色模式'
+        : '🌓 切换暗色模式';
+    });
+
+    const githubUser = 'like017';
+    const box = document.getElementById('githubSec');
+    fetch(`https://api.github.com/users/${githubUser}`)
+      .then(r => r.json())
+      .then(d => {
+        box.innerHTML = `
+          <h2>GitHub 实时数据</h2>
+          <img src="${d.avatar_url}" width="80" style="border-radius:50%">
+          <p>用户名：${d.login}</p>
+          <p>公开仓库：${d.public_repos}</p>
+          <p>粉丝数：${d.followers}</p>
+        `;
+      })
+      .catch(() => {
+        box.innerHTML = '<h2>GitHub 实时数据</h2><p>获取失败，请检查网络</p>';
+      });
+  </script>
+</body>
+</html>
diff --git a/frontend/public/home.html b/frontend/public/home.html
new file mode 100644
index 0000000..c647805
--- /dev/null
+++ b/frontend/public/home.html
@@ -0,0 +1,39 @@
+<!DOCTYPE html>
+<html lang="zh-CN">
+<head>
+  <meta charset="UTF-8">
+  <title>我的首页</title>
+  <style>
+    html,body{height:100%;margin:0;}
+    body{
+      background:url('https://i.ibb.co/t1WZsMD/301e4a1856b68d86f90271f769c1c942.png') center/cover no-repeat fixed;
+      position:relative;            
+      color:#fff;                     
+      font:32px/1.4 Arial,sans-serif;
+      text-align:center;
+      display:table;              
+      width:100%;
+    }
+    body::before{               
+      content:"";
+      position:absolute;
+      inset:0;
+      background:rgba(0,0,0,.5);
+    }
+    .center{                         
+      display:table-cell;
+      vertical-align:middle;
+      position:relative;           
+      z-index:1;
+    }
+    a{color:#1e90ff;text-decoration:none;}
+    a:hover{text-decoration:underline;}
+  </style>
+</head>
+<body>
+  <div class="center">
+    <h1>欢迎来到我的主页</h1>
+    <p>点击这里查看 <a href="about-me.html">关于我</a></p>
+  </div>
+</body>
+</html>
\ No newline at end of file