diff --git a/src/common/hooks/useSse.ts b/src/common/hooks/useSse.ts
index 866e2e6..3a203e3 100644
--- a/src/common/hooks/useSse.ts
+++ b/src/common/hooks/useSse.ts
@@ -6,16 +6,16 @@ import { useAccountStore } from '@/stores/modules/account'
 /**
  * SSE 连接管理 composable（基于 @microsoft/fetch-event-source）
  *
- * 登录后调用 connect() 建立全局唯一的 SSE 长连接。
- * 收到服务端事件后解析 JSON 并通过 sseBus 分发给订阅者。
- *
- * 鉴权：通过 fetch-event-source 的 headers 传 saToken，和 axios 走同一套机制。
- * 401 时精确读取 err.response.status 触发 token 刷新，刷新成功自动重连。
+ * 设计原则：
+ * - 全局唯一：同一时间只有一条活跃的 SSE 连接
+ * - token 驱动：仅 accessToken 变更时才断开重连
+ * - 防重复：已连接（相同 token）时 connect() 直接跳过
+ * - 所有业务变更通过 sseBus 事件总线推送，各组件自行订阅
  *
  * 使用示例：
  * ```ts
  * const { isConnected, connect, disconnect } = useSse()
- * watch(() => userStore.accessToken, (v) => v ? connect() : disconnect())
+ * watch(() => accountStore.accessToken, (v) => v ? connect() : disconnect())
  * ```
  */
 export function useSse() {
@@ -23,6 +23,10 @@ export function useSse() {
   const isConnected = ref(false)
   /** 用于取消 inflight 连接的控制器 */
   let abortController: AbortController | null = null
+  /** 当前连接使用的 token（用于判断是否需要重连） */
+  let currentToken: string | null = null
+  /** 是否正在建立连接（防并发） */
+  let connecting = false
   /** 当前连接的重试计数 */
   let retryCount = 0
   /** 是否正在刷新 token（防并发） */
@@ -33,6 +37,8 @@ export function useSse() {
    *
    * 通过 fetch-event-source 发起，设置 saToken 请求头鉴权。
    * 连接期间持续接收服务端推送事件，直到 abort 或服务端关闭。
+   *
+   * 防重复：如果已用相同 token 连接或正在连接中，直接跳过。
    */
   async function connect(): Promise<void> {
     const accountStore = useAccountStore()
@@ -42,9 +48,16 @@ export function useSse() {
       return
     }
 
-    // 取消上一次连接
+    // 相同 token 已连接或正在连接中，跳过
+    if (currentToken === token && (isConnected.value || connecting)) {
+      return
+    }
+
+    // 取消旧连接
     abort()
 
+    connecting = true
+    currentToken = token
     abortController = new AbortController()
 
     // Vite 代理: /api/sse/subscribe → 后端 /sse/subscribe
@@ -54,6 +67,7 @@ export function useSse() {
 
       /** 连接建立 */
       async onopen() {
+        connecting = false
         isConnected.value = true
         retryCount = 0
         console.log('[SSE] 连接已建立')
@@ -75,6 +89,7 @@ export function useSse() {
 
       /** 连接关闭 */
       onclose() {
+        connecting = false
         isConnected.value = false
         console.log('[SSE] 连接已关闭')
       },
@@ -87,6 +102,7 @@ export function useSse() {
        * 其他错误 → 返回重试延迟（ms），库自动排队重连
        */
       onerror(err) {
+        connecting = false
         isConnected.value = false
 
         // 鉴权失败 → 刷新 token（异步 fire-and-forget，onerror 本身保持同步）
@@ -135,7 +151,7 @@ export function useSse() {
           throw err // 超过阈值，停止重连
         }
 
-        // 返回重试间隔（ms），指数退避：3s, 6s, 12s, 24s
+        // 返回重试间隔（ms），指数退避：3s, 6s, 12s, 24s，最大 30s
         const delay = Math.min(3000 * Math.pow(2, retryCount - 1), 30000)
         console.warn(`[SSE] 连接错误，${delay / 1000}s 后重试 (${retryCount}/5)`)
         return delay
@@ -151,7 +167,9 @@ export function useSse() {
       abortController.abort()
       abortController = null
     }
+    connecting = false
     isConnected.value = false
+    currentToken = null
     retryCount = 0
   }
 
diff --git a/src/common/websocket/roomSocket.ts b/src/common/websocket/roomSocket.ts
index 28d1952..bafcf2f 100644
--- a/src/common/websocket/roomSocket.ts
+++ b/src/common/websocket/roomSocket.ts
@@ -56,6 +56,10 @@ export function createRoomSocket(
   let intentionalClose = false
   /** 重连定时器 ID，用于组件卸载时取消 */
   let reconnectTimer: ReturnType<typeof setTimeout> | null = null
+  /** 消息发送队列（连接未就绪时暂存） */
+  let messageQueue: Array<{ type: string; data?: unknown }> = []
+  /** 最大排队消息数 */
+  const MAX_QUEUE_SIZE = 50
 
   /** 建立 WebSocket 连接 */
   function connect(): void {
@@ -68,6 +72,12 @@ export function createRoomSocket(
     ws = new WebSocket(wsUrl)
 
     ws.onopen = () => {
+      // 用户已离开，直接关闭连接
+      if (intentionalClose) {
+        ws?.close(1000, '用户已离开')
+        return
+      }
+
       // eslint-disable-next-line no-console
       console.log('[WS] 房间连接已建立, roomId=', roomId)
       if (retryCount > 0) {
@@ -79,6 +89,9 @@ export function createRoomSocket(
       } else {
         callbacks.onOpen?.()
       }
+
+      // 刷新排队中的消息
+      flushQueue()
     }
 
     ws.onclose = (event) => {
@@ -135,10 +148,31 @@ export function createRoomSocket(
   // 初始连接
   connect()
 
+  /** 刷新消息发送队列 */
+  function flushQueue(): void {
+    if (messageQueue.length === 0) return
+    // eslint-disable-next-line no-console
+    console.log(`[WS] 刷新排队消息, count=${messageQueue.length}`)
+    const pending = messageQueue
+    messageQueue = []
+    for (const msg of pending) {
+      if (ws && ws.readyState === WebSocket.OPEN) {
+        ws.send(JSON.stringify(msg))
+      }
+    }
+  }
+
   return {
     send(type: string, data?: unknown) {
       if (ws && ws.readyState === WebSocket.OPEN) {
         ws.send(JSON.stringify({ type, data }))
+      } else if (ws && ws.readyState === WebSocket.CONNECTING) {
+        // 连接尚未就绪，排队等待
+        if (messageQueue.length < MAX_QUEUE_SIZE) {
+          messageQueue.push({ type, data })
+        }
+      } else {
+        console.warn(`[WS] 消息未发送（连接未就绪）, type=${type}, readyState=${ws?.readyState ?? 'null'}`)
       }
     },
     close() {
@@ -149,8 +183,10 @@ export function createRoomSocket(
         reconnectTimer = null
       }
       if (ws) {
-        ws.close(1000, '用户离开')
-        ws = null
+        // 仅 OPEN 状态可安全关闭，CONNECTING 时由 onopen 处理
+        if (ws.readyState === WebSocket.OPEN) {
+          ws.close(1000, '用户离开')
+        }
       }
     },
     isOpen() {
diff --git a/src/stores/modules/room.ts b/src/stores/modules/room.ts
index 70ae6a5..face7ba 100644
--- a/src/stores/modules/room.ts
+++ b/src/stores/modules/room.ts
@@ -101,7 +101,20 @@ export const useRoomStore = defineStore('room', () => {
   }
 
   /** 添加聊天消息 */
+  /** 添加聊天消息（自动去重：同用户同内容 2 秒内只保留一条） */
   function addMessage(msg: ChatMessage) {
+    // 去重：检查最后一条消息是否与即将添加的相同
+    const last = messages.value[messages.value.length - 1]
+    if (
+      last &&
+      last.userId === msg.userId &&
+      last.content === msg.content &&
+      Math.abs(last.timestamp - msg.timestamp) < 2000
+    ) {
+      // 用后端的时间戳更新（更准确），其它不变
+      last.timestamp = msg.timestamp
+      return
+    }
     messages.value.push(msg)
   }
 
diff --git a/src/views/game/components/GomokuBoard.vue b/src/views/game/components/GomokuBoard.vue
index 5209e9a..667a728 100644
--- a/src/views/game/components/GomokuBoard.vue
+++ b/src/views/game/components/GomokuBoard.vue
@@ -29,7 +29,7 @@ const canvasSize = PADDING * 2 + CELL_SIZE * (BOARD_SIZE - 1)
 
 const store = useRoomStore()
 const { boardState, currentTurn, currentUserId, isPlayer, isPlaying } = storeToRefs(store)
-const socket = inject<RoomSocket>('roomSocket', null)!
+const socket = inject<RoomSocket>('roomSocket')!
 
 const canvasRef = ref<HTMLCanvasElement | null>(null)
 const hoverPos = ref<{ row: number; col: number } | null>(null)
@@ -101,8 +101,9 @@ function drawBoard() {
   if (board) {
     for (let r = 0; r < BOARD_SIZE; r++) {
       for (let c = 0; c < BOARD_SIZE; c++) {
-        if (board[r] && board[r][c]) {
-          drawStone(ctx, r, c, board[r][c] === 1 ? '#1a1a1a' : '#f5f5f5')
+        const stone = board[r]?.[c]
+        if (stone) {
+          drawStone(ctx, r, c, stone === 1 ? '#1a1a1a' : '#f5f5f5')
         }
       }
     }
@@ -123,7 +124,7 @@ function drawBoard() {
   // ---- 最后一手标记（红色圆圈） ----
   const moves = store.moves
   if (moves.length > 0) {
-    const lastMove = moves[moves.length - 1]
+    const lastMove = moves[moves.length - 1]!
     const x = PADDING + lastMove.col * CELL_SIZE
     const y = PADDING + lastMove.row * CELL_SIZE
     ctx.strokeStyle = '#E74C3C'
diff --git a/src/views/game/components/RoomActions.vue b/src/views/game/components/RoomActions.vue
index c047e51..7749728 100644
--- a/src/views/game/components/RoomActions.vue
+++ b/src/views/game/components/RoomActions.vue
@@ -63,7 +63,7 @@ const { players, currentUserId } = storeToRefs(store)
 const router = useRouter()
 
 /** 通过 inject 获取 WS 连接（父组件 provide） */
-const socket = inject<RoomSocket>('roomSocket', null)!
+const socket = inject<RoomSocket>('roomSocket')!
 
 /** 当前用户是否已准备 */
 const isReady = computed(() => {
diff --git a/src/views/game/components/RoomChat.vue b/src/views/game/components/RoomChat.vue
index a8abf21..d9589db 100644
--- a/src/views/game/components/RoomChat.vue
+++ b/src/views/game/components/RoomChat.vue
@@ -2,13 +2,21 @@
   <div class="room-chat">
     <!-- 消息列表 -->
     <div ref="messagesContainer" class="room-chat__messages">
-      <div v-for="(msg, idx) in store.messages" :key="idx" class="room-chat__msg">
-        <span class="room-chat__msg-user">{{ msg.userId === store.currentUserId ? '我' : getUserName(msg.userId) }}</span>
-        <span class="room-chat__msg-text">{{ msg.content }}</span>
-      </div>
-      <div v-if="store.messages.length === 0" class="room-chat__empty">
-        暂无消息
+      <div
+        v-for="(msg, idx) in store.messages"
+        :key="idx"
+        class="room-chat__msg"
+        :class="{ 'room-chat__msg--self': msg.userId === store.currentUserId }"
+      >
+        <div class="room-chat__msg-meta">
+          <span class="room-chat__msg-user">{{
+            msg.userId === store.currentUserId ? '我' : getUserName(msg.userId)
+          }}</span>
+          <span class="room-chat__msg-time">{{ formatTime(msg.timestamp) }}</span>
+        </div>
+        <div class="room-chat__msg-bubble">{{ msg.content }}</div>
       </div>
+      <div v-if="store.messages.length === 0" class="room-chat__empty">暂无消息</div>
     </div>
 
     <!-- 输入区 -->
@@ -17,9 +25,15 @@
         v-model="input"
         class="room-chat__input"
         placeholder="输入消息..."
-        maxlength="200"
+        :maxlength="CHAT_MAX_LENGTH"
         @keyup.enter="sendMessage"
       />
+      <span
+        class="room-chat__char-count"
+        :class="{ 'room-chat__char-count--warn': input.length > CHAT_MAX_LENGTH * 0.8 }"
+      >
+        {{ input.length }}/{{ CHAT_MAX_LENGTH }}
+      </span>
       <button class="room-chat__send-btn" @click="sendMessage">发送</button>
     </div>
   </div>
@@ -31,9 +45,12 @@ import { useRoomStore } from '@/stores'
 import { storeToRefs } from 'pinia'
 import type { RoomSocket } from '@/common/websocket/roomSocket'
 
+/** 聊天最大字符数（与后端 CHAT_MAX_LENGTH 保持一致） */
+const CHAT_MAX_LENGTH = 500
+
 const store = useRoomStore()
 const { messages, players } = storeToRefs(store)
-const socket = inject<RoomSocket>('roomSocket', null)
+const socket = inject<RoomSocket>('roomSocket')
 
 /** 发送消息（空安全，socket 尚未建立时静默丢弃） */
 function safeSend(type: string, data?: unknown) {
@@ -48,19 +65,39 @@ const messagesContainer = ref<HTMLElement>()
 /**
  * 监听消息列表变化，自动滚动到底部
  */
-watch(() => messages.value.length, async () => {
-  await nextTick()
+watch(
+  () => messages.value.length,
+  async () => {
+    await nextTick()
+    scrollToBottom()
+  }
+)
+
+/**
+ * 滚动到消息列表底部
+ */
+function scrollToBottom() {
   if (messagesContainer.value) {
     messagesContainer.value.scrollTop = messagesContainer.value.scrollHeight
   }
-})
+}
 
-/** 发送聊天消息 */
+/** 发送聊天消息（乐观更新：先显示在本地，再通过 WS 发送） */
 function sendMessage() {
   const content = input.value.trim()
-  if (!content) return
-  safeSend('chat', { content })
+  if (!content || content.length > CHAT_MAX_LENGTH) return
+
+  // 乐观更新：立即添加到本地消息列表
+  const localMsg = {
+    userId: store.currentUserId,
+    content,
+    timestamp: Date.now()
+  }
+  store.addMessage(localMsg)
   input.value = ''
+
+  // 通过 WS 发送，广播回来自动去重
+  safeSend('chat', { content })
 }
 
 /**
@@ -70,7 +107,20 @@ function sendMessage() {
  */
 function getUserName(userId: string): string {
   const player = players.value.find((p) => p.userId === userId)
-  return player?.nickname ?? '未知用户'
+  return player?.nickname ?? '观战者'
+}
+
+/**
+ * 格式化时间戳为 HH:mm
+ * @param ts 毫秒时间戳
+ * @returns 格式化后的时间字符串
+ */
+function formatTime(ts: number): string {
+  if (!ts) return ''
+  const d = new Date(ts)
+  const hh = String(d.getHours()).padStart(2, '0')
+  const mm = String(d.getMinutes()).padStart(2, '0')
+  return `${hh}:${mm}`
 }
 </script>
 
@@ -87,22 +137,63 @@ function getUserName(userId: string): string {
   overflow-y: auto;
   display: flex;
   flex-direction: column;
-  gap: 6px;
+  gap: 8px;
 }
 
 .room-chat__msg {
-  font-size: 13px;
-  line-height: 1.5;
+  display: flex;
+  flex-direction: column;
+  gap: 2px;
+  max-width: 85%;
+
+  &--self {
+    align-self: flex-end;
+
+    .room-chat__msg-bubble {
+      background-color: var(--color-primary);
+      color: var(--text-inverse);
+      border-radius: 10px 10px 2px 10px;
+    }
+
+    .room-chat__msg-meta {
+      flex-direction: row-reverse;
+    }
+  }
+
+  &:not(&--self) {
+    align-self: flex-start;
+
+    .room-chat__msg-bubble {
+      background-color: var(--bg-surface-hover);
+      color: var(--text-primary);
+      border-radius: 10px 10px 10px 2px;
+    }
+  }
+}
+
+.room-chat__msg-meta {
+  display: flex;
+  align-items: center;
+  gap: 6px;
+  padding: 0 4px;
 }
 
 .room-chat__msg-user {
+  font-size: 11px;
   font-weight: 600;
-  color: var(--color-primary);
-  margin-right: 6px;
+  color: var(--text-secondary);
 }
 
-.room-chat__msg-text {
-  color: var(--text-primary);
+.room-chat__msg-time {
+  font-size: 10px;
+  color: var(--text-tertiary);
+}
+
+.room-chat__msg-bubble {
+  padding: 6px 10px;
+  font-size: 13px;
+  line-height: 1.5;
+  word-break: break-word;
 }
 
 .room-chat__empty {
@@ -114,7 +205,8 @@ function getUserName(userId: string): string {
 
 .room-chat__input-area {
   display: flex;
-  gap: 8px;
+  align-items: center;
+  gap: 6px;
   padding: 10px;
   border-top: 1px solid var(--border-light);
 }
@@ -134,6 +226,18 @@ function getUserName(userId: string): string {
   }
 }
 
+.room-chat__char-count {
+  font-size: 11px;
+  color: var(--text-tertiary);
+  min-width: 42px;
+  text-align: right;
+  transition: color 0.15s ease;
+
+  &--warn {
+    color: var(--color-warning);
+  }
+}
+
 .room-chat__send-btn {
   padding: 6px 14px;
   border: none;
@@ -142,9 +246,14 @@ function getUserName(userId: string): string {
   color: var(--text-inverse);
   font-size: 13px;
   cursor: pointer;
+  white-space: nowrap;
 
   &:hover {
     background-color: var(--color-primary-hover);
   }
+
+  &:active {
+    transform: scale(0.97);
+  }
 }
 </style>