diff --git a/apps/dashboard/src/App.tsx b/apps/dashboard/src/App.tsx
index ba961af..3a71d89 100644
--- a/apps/dashboard/src/App.tsx
+++ b/apps/dashboard/src/App.tsx
@@ -34,7 +34,6 @@ import {
   fetchAccounts,
   fetchDashboardData,
   fetchModelConfig,
-  fetchRoomsTimelineBatch,
   runInboxAction,
   runServiceAction,
   runScheduledTaskAction,
@@ -52,6 +51,10 @@ import {
   type Locale,
   type Messages,
 } from './i18n';
+import {
+  useSelectedRoomActivity,
+  type RoomActivityMap,
+} from './useRoomActivity';
 import './styles.css';
 
 interface DashboardState {
@@ -60,8 +63,6 @@ interface DashboardState {
   tasks: DashboardTask[];
 }
 
-type RoomActivityMap = Record<string, DashboardRoomActivity>;
-
 type UsageRow = DashboardOverview['usage']['rows'][number];
 type InboxItem = DashboardOverview['inbox'][number];
 type RiskLevel = 'ok' | 'warn' | 'critical';
@@ -2568,7 +2569,9 @@ function RoomBoardV2({
   roomActivity,
   roomActivityLoading,
   roomMessageKey,
+  selectedJid,
   locale,
+  onSelectedJidChange,
   snapshots,
   t,
 }: {
@@ -2585,13 +2588,14 @@ function RoomBoardV2({
   roomActivity: RoomActivityMap;
   roomActivityLoading: boolean;
   roomMessageKey: string | null;
+  selectedJid: string | null;
   locale: Locale;
+  onSelectedJidChange: (jid: string | null) => void;
   snapshots: StatusSnapshot[];
   t: Messages;
 }) {
   const [filter, setFilter] = useState<RoomFilter>('all');
   const [sort, setSort] = useState<RoomSort>('recent');
-  const [selectedJid, setSelectedJid] = useState<string | null>(null);
   const [drafts, setDrafts] = useState<Record<string, string>>({});
 
   const allEntries: RoomEntryWithService[] = snapshots.flatMap((snapshot) =>
@@ -2601,10 +2605,6 @@ function RoomBoardV2({
     })),
   );
 
-  if (allEntries.length === 0) {
-    return <EmptyState>{t.rooms.empty}</EmptyState>;
-  }
-
   const counts = {
     all: allEntries.length,
     processing: allEntries.filter((e) => e.status === 'processing').length,
@@ -2632,6 +2632,15 @@ function RoomBoardV2({
   const selectedEntry =
     sorted.find((e) => e.jid === selectedJid) ?? sorted[0] ?? null;
 
+  useEffect(() => {
+    const nextJid = selectedEntry?.jid ?? null;
+    if (nextJid !== selectedJid) onSelectedJidChange(nextJid);
+  }, [onSelectedJidChange, selectedEntry?.jid, selectedJid]);
+
+  if (allEntries.length === 0) {
+    return <EmptyState>{t.rooms.empty}</EmptyState>;
+  }
+
   function setDraft(jid: string, value: string) {
     setDrafts((previous) => ({ ...previous, [jid]: value }));
   }
@@ -2705,7 +2714,7 @@ function RoomBoardV2({
                   aria-current={active ? 'page' : undefined}
                   className={`rooms-list-item status-${entry.status}${active ? ' is-active' : ''}`}
                   key={`${entry.serviceId}:${entry.jid}`}
-                  onClick={() => setSelectedJid(entry.jid)}
+                  onClick={() => onSelectedJidChange(entry.jid)}
                   type="button"
                 >
                   <span className={`room-pulse pulse-${entry.status}`}>
@@ -3788,8 +3797,15 @@ function App() {
   const [serviceActionKey, setServiceActionKey] =
     useState<ServiceActionKey | null>(null);
   const [roomMessageKey, setRoomMessageKey] = useState<string | null>(null);
-  const [roomActivity, setRoomActivity] = useState<RoomActivityMap>({});
-  const [roomActivityLoading, setRoomActivityLoading] = useState(false);
+  const [selectedRoomJid, setSelectedRoomJid] = useState<string | null>(null);
+  const {
+    refreshRoom: refreshRoomActivity,
+    roomActivity,
+    roomActivityLoading,
+  } = useSelectedRoomActivity({
+    active: activeView === 'rooms',
+    selectedRoomJid: selectedRoomJid,
+  });
   const [pendingMessages, setPendingMessages] = useState<
     Record<string, Array<DashboardRoomActivity['messages'][number]>>
   >({});
@@ -3956,8 +3972,7 @@ function App() {
     try {
       await sendRoomMessage(roomJid, text, requestId, nickname || null);
       try {
-        const fresh = await fetchRoomsTimelineBatch();
-        setRoomActivity(fresh);
+        await refreshRoomActivity(roomJid);
       } catch {
         /* refresh will retry on next poll */
       }
@@ -4125,102 +4140,6 @@ function App() {
     return () => window.clearInterval(id);
   }, []);
 
-  const roomsJidsKey = useMemo(() => {
-    if (!data) return '';
-    return [
-      ...new Set(
-        data.snapshots.flatMap((snapshot) =>
-          snapshot.entries.map((entry) => entry.jid),
-        ),
-      ),
-    ]
-      .sort()
-      .join('|');
-  }, [data]);
-
-  const roomsLastUpdatedKey = useMemo(() => {
-    if (!data) return '';
-    return data.snapshots
-      .map((s) => s.updatedAt)
-      .sort()
-      .join('|');
-  }, [data]);
-
-  useEffect(() => {
-    if (activeView !== 'rooms' || !data) return;
-    if (!roomsJidsKey) {
-      setRoomActivity({});
-      return;
-    }
-
-    let cancelled = false;
-    let inFlight = false;
-    let pollIntervalId: number | null = null;
-    let es: EventSource | null = null;
-
-    const applyMap = (map: RoomActivityMap) => {
-      if (!cancelled) setRoomActivity(map);
-    };
-
-    const fetchOnce = async (initial: boolean) => {
-      if (cancelled || inFlight) return;
-      inFlight = true;
-      if (initial) setRoomActivityLoading(true);
-      try {
-        applyMap(await fetchRoomsTimelineBatch());
-      } catch {
-        /* keep last good state */
-      } finally {
-        inFlight = false;
-        if (!cancelled && initial) setRoomActivityLoading(false);
-      }
-    };
-
-    const startPollingFallback = () => {
-      if (pollIntervalId !== null) return;
-      pollIntervalId = window.setInterval(() => void fetchOnce(false), 2000);
-    };
-
-    const stopPollingFallback = () => {
-      if (pollIntervalId === null) return;
-      window.clearInterval(pollIntervalId);
-      pollIntervalId = null;
-    };
-
-    if (typeof window !== 'undefined' && 'EventSource' in window) {
-      void fetchOnce(true);
-      try {
-        es = new EventSource('/api/stream');
-        es.addEventListener('rooms-timeline', (event) => {
-          try {
-            const parsed = JSON.parse(
-              (event as MessageEvent).data,
-            ) as RoomActivityMap;
-            applyMap(parsed);
-            stopPollingFallback();
-          } catch {
-            /* malformed event, ignore */
-          }
-        });
-        es.onerror = () => {
-          // Browser auto-reconnects; meanwhile keep data fresh via polling.
-          startPollingFallback();
-        };
-      } catch {
-        startPollingFallback();
-      }
-    } else {
-      void fetchOnce(true);
-      startPollingFallback();
-    }
-
-    return () => {
-      cancelled = true;
-      stopPollingFallback();
-      es?.close();
-    };
-  }, [activeView, roomsJidsKey]);
-
   useEffect(() => {
     setPendingMessages((prev) => {
       const next: typeof prev = {};
@@ -4385,6 +4304,8 @@ function App() {
                   roomActivityLoading={roomActivityLoading}
                   roomMessageKey={roomMessageKey}
                   locale={locale}
+                  onSelectedJidChange={setSelectedRoomJid}
+                  selectedJid={selectedRoomJid}
                   snapshots={data.snapshots}
                   t={t}
                 />
diff --git a/apps/dashboard/src/i18n.ts b/apps/dashboard/src/i18n.ts
index 97fe4de..5279c90 100644
--- a/apps/dashboard/src/i18n.ts
+++ b/apps/dashboard/src/i18n.ts
@@ -1,3 +1,5 @@
+import { roomMessages, type RoomMessages } from './i18n/rooms';
+
 export const LOCALES = ['ko', 'en', 'zh', 'ja'] as const;
 
 export type Locale = (typeof LOCALES)[number];
@@ -152,46 +154,7 @@ export interface Messages {
       confirmDecline: string;
     };
   };
-  rooms: {
-    empty: string;
-    cardsAria: string;
-    room: string;
-    service: string;
-    agent: string;
-    status: string;
-    queue: string;
-    queueWaitingMessages: string;
-    tasks: string;
-    elapsed: string;
-    activity: string;
-    loadingActivity: string;
-    noActivity: string;
-    task: string;
-    noTask: string;
-    currentTurn: string;
-    noTurn: string;
-    round: string;
-    attempt: string;
-    updated: string;
-    output: string;
-    latestOutput: string;
-    outputHistory: string;
-    noOutput: string;
-    recentMessages: string;
-    messageHistory: string;
-    noMessages: string;
-    details: string;
-    message: string;
-    messagePlaceholder: string;
-    send: string;
-    sending: string;
-    error: string;
-    filterAll: string;
-    sortRecent: string;
-    sortName: string;
-    sortQueue: string;
-    sortLabel: string;
-  };
+  rooms: RoomMessages;
   usage: {
     empty: string;
     current: string;
@@ -465,46 +428,7 @@ export const messages = {
         confirmDecline: 'Decline this item?',
       },
     },
-    rooms: {
-      empty: '룸 없음.',
-      cardsAria: '룸 상태 카드',
-      room: '룸',
-      service: '서비스',
-      agent: '에이전트',
-      status: '상태',
-      queue: '큐',
-      queueWaitingMessages: '대기 메시지',
-      tasks: '태스크',
-      elapsed: '경과',
-      activity: '진행',
-      loadingActivity: '진행 로딩 중',
-      noActivity: '진행 없음',
-      task: '태스크',
-      noTask: '태스크 없음',
-      currentTurn: '현재 턴',
-      noTurn: '턴 없음',
-      round: '라운드',
-      attempt: '시도',
-      updated: '갱신',
-      output: '출력',
-      latestOutput: '마지막 출력',
-      outputHistory: '출력 기록',
-      noOutput: '출력 없음',
-      recentMessages: '메시지 기록',
-      messageHistory: '메시지 기록',
-      noMessages: '메시지 없음',
-      details: '세부',
-      message: '메시지',
-      messagePlaceholder: '요청 입력...',
-      send: '전송',
-      sending: '전송 중...',
-      error: '오류',
-      filterAll: '전체',
-      sortRecent: '최근 활동',
-      sortName: '이름순',
-      sortQueue: '큐 많은 순',
-      sortLabel: '정렬',
-    },
+    rooms: roomMessages.ko,
     usage: {
       empty: '사용량 스냅샷 없음. 수집기 확인.',
       current: '사용중',
@@ -762,46 +686,7 @@ export const messages = {
         confirmDecline: 'Decline this item?',
       },
     },
-    rooms: {
-      empty: 'No rooms yet.',
-      cardsAria: 'Room status cards',
-      room: 'room',
-      service: 'service',
-      agent: 'agent',
-      status: 'status',
-      queue: 'queue',
-      queueWaitingMessages: 'pending messages',
-      tasks: 'tasks',
-      elapsed: 'elapsed',
-      activity: 'activity',
-      loadingActivity: 'Loading activity',
-      noActivity: 'No activity',
-      task: 'task',
-      noTask: 'No task',
-      currentTurn: 'Current turn',
-      noTurn: 'No turn',
-      round: 'round',
-      attempt: 'attempt',
-      updated: 'updated',
-      output: 'output',
-      latestOutput: 'latest output',
-      outputHistory: 'output log',
-      noOutput: 'No output',
-      recentMessages: 'Message log',
-      messageHistory: 'Message log',
-      noMessages: 'No messages',
-      details: 'details',
-      message: 'message',
-      messagePlaceholder: 'Type request...',
-      send: 'Send',
-      sending: 'Sending',
-      error: 'Error',
-      filterAll: 'All',
-      sortRecent: 'Recent activity',
-      sortName: 'Name',
-      sortQueue: 'Queue size',
-      sortLabel: 'Sort',
-    },
+    rooms: roomMessages.en,
     usage: {
       empty: 'No usage snapshot. Check collector.',
       current: 'Active',
@@ -1059,46 +944,7 @@ export const messages = {
         confirmDecline: '确认拒绝此项？',
       },
     },
-    rooms: {
-      empty: '暂无房间。',
-      cardsAria: '房间状态卡片',
-      room: '房间',
-      service: '服务',
-      agent: '代理',
-      status: '状态',
-      queue: '队列',
-      queueWaitingMessages: '待处理消息',
-      tasks: '任务',
-      elapsed: '耗时',
-      activity: '进展',
-      loadingActivity: '正在加载进展',
-      noActivity: '暂无进展',
-      task: '任务',
-      noTask: '无任务',
-      currentTurn: '当前回合',
-      noTurn: '无回合',
-      round: '轮次',
-      attempt: '尝试',
-      updated: '更新',
-      output: '输出',
-      latestOutput: '最新输出',
-      outputHistory: '输出记录',
-      noOutput: '暂无输出',
-      recentMessages: '消息记录',
-      messageHistory: '消息记录',
-      noMessages: '暂无消息',
-      details: '详情',
-      message: 'Message',
-      messagePlaceholder: '输入请求...',
-      send: '发送',
-      sending: '发送中...',
-      error: '错误',
-      filterAll: '全部',
-      sortRecent: '最近活动',
-      sortName: '名称',
-      sortQueue: '队列大小',
-      sortLabel: '排序',
-    },
+    rooms: roomMessages.zh,
     usage: {
       empty: '暂无用量快照。检查采集器。',
       current: '使用中',
@@ -1358,46 +1204,7 @@ export const messages = {
         confirmDecline: 'この項目を拒否しますか？',
       },
     },
-    rooms: {
-      empty: 'ルームなし。',
-      cardsAria: 'ルーム状態カード',
-      room: 'ルーム',
-      service: 'サービス',
-      agent: 'エージェント',
-      status: '状態',
-      queue: 'キュー',
-      queueWaitingMessages: '待機メッセージ',
-      tasks: 'タスク',
-      elapsed: '経過',
-      activity: '進行',
-      loadingActivity: '進行を読み込み中',
-      noActivity: '進行なし',
-      task: 'タスク',
-      noTask: 'タスクなし',
-      currentTurn: '現在ターン',
-      noTurn: 'ターンなし',
-      round: 'ラウンド',
-      attempt: '試行',
-      updated: '更新',
-      output: '出力',
-      latestOutput: '最新出力',
-      outputHistory: '出力履歴',
-      noOutput: '出力なし',
-      recentMessages: 'メッセージ履歴',
-      messageHistory: 'メッセージ履歴',
-      noMessages: 'メッセージなし',
-      details: '詳細',
-      message: 'メッセージ',
-      messagePlaceholder: '依頼を入力...',
-      send: '送信',
-      sending: '送信中...',
-      error: 'エラー',
-      filterAll: '全て',
-      sortRecent: '最近の活動',
-      sortName: '名前順',
-      sortQueue: 'キュー順',
-      sortLabel: '並び替え',
-    },
+    rooms: roomMessages.ja,
     usage: {
       empty: '使用量スナップショットなし。収集器を確認。',
       current: '使用中',
diff --git a/apps/dashboard/src/i18n/rooms.ts b/apps/dashboard/src/i18n/rooms.ts
new file mode 100644
index 0000000..2ff27ed
--- /dev/null
+++ b/apps/dashboard/src/i18n/rooms.ts
@@ -0,0 +1,205 @@
+import type { Locale } from '../i18n';
+
+export interface RoomMessages {
+  empty: string;
+  cardsAria: string;
+  room: string;
+  service: string;
+  agent: string;
+  status: string;
+  queue: string;
+  queueWaitingMessages: string;
+  tasks: string;
+  elapsed: string;
+  activity: string;
+  loadingActivity: string;
+  noActivity: string;
+  task: string;
+  noTask: string;
+  currentTurn: string;
+  noTurn: string;
+  round: string;
+  attempt: string;
+  updated: string;
+  output: string;
+  latestOutput: string;
+  outputHistory: string;
+  noOutput: string;
+  recentMessages: string;
+  messageHistory: string;
+  noMessages: string;
+  details: string;
+  message: string;
+  messagePlaceholder: string;
+  send: string;
+  sending: string;
+  error: string;
+  filterAll: string;
+  sortRecent: string;
+  sortName: string;
+  sortQueue: string;
+  sortLabel: string;
+}
+
+export const roomMessages = {
+  ko: {
+    empty: '룸 없음.',
+    cardsAria: '룸 상태 카드',
+    room: '룸',
+    service: '서비스',
+    agent: '에이전트',
+    status: '상태',
+    queue: '큐',
+    queueWaitingMessages: '대기 메시지',
+    tasks: '태스크',
+    elapsed: '경과',
+    activity: '진행',
+    loadingActivity: '진행 로딩 중',
+    noActivity: '진행 없음',
+    task: '태스크',
+    noTask: '태스크 없음',
+    currentTurn: '현재 턴',
+    noTurn: '턴 없음',
+    round: '라운드',
+    attempt: '시도',
+    updated: '갱신',
+    output: '출력',
+    latestOutput: '마지막 출력',
+    outputHistory: '출력 기록',
+    noOutput: '출력 없음',
+    recentMessages: '메시지 기록',
+    messageHistory: '메시지 기록',
+    noMessages: '메시지 없음',
+    details: '세부',
+    message: '메시지',
+    messagePlaceholder: '요청 입력...',
+    send: '전송',
+    sending: '전송 중...',
+    error: '오류',
+    filterAll: '전체',
+    sortRecent: '최근 활동',
+    sortName: '이름순',
+    sortQueue: '큐 많은 순',
+    sortLabel: '정렬',
+  },
+  en: {
+    empty: 'No rooms yet.',
+    cardsAria: 'Room status cards',
+    room: 'room',
+    service: 'service',
+    agent: 'agent',
+    status: 'status',
+    queue: 'queue',
+    queueWaitingMessages: 'pending messages',
+    tasks: 'tasks',
+    elapsed: 'elapsed',
+    activity: 'activity',
+    loadingActivity: 'Loading activity',
+    noActivity: 'No activity',
+    task: 'task',
+    noTask: 'No task',
+    currentTurn: 'Current turn',
+    noTurn: 'No turn',
+    round: 'round',
+    attempt: 'attempt',
+    updated: 'updated',
+    output: 'output',
+    latestOutput: 'latest output',
+    outputHistory: 'output log',
+    noOutput: 'No output',
+    recentMessages: 'Message log',
+    messageHistory: 'Message log',
+    noMessages: 'No messages',
+    details: 'details',
+    message: 'message',
+    messagePlaceholder: 'Type request...',
+    send: 'Send',
+    sending: 'Sending',
+    error: 'Error',
+    filterAll: 'All',
+    sortRecent: 'Recent activity',
+    sortName: 'Name',
+    sortQueue: 'Queue size',
+    sortLabel: 'Sort',
+  },
+  zh: {
+    empty: '暂无房间。',
+    cardsAria: '房间状态卡片',
+    room: '房间',
+    service: '服务',
+    agent: '代理',
+    status: '状态',
+    queue: '队列',
+    queueWaitingMessages: '待处理消息',
+    tasks: '任务',
+    elapsed: '耗时',
+    activity: '进展',
+    loadingActivity: '正在加载进展',
+    noActivity: '暂无进展',
+    task: '任务',
+    noTask: '无任务',
+    currentTurn: '当前回合',
+    noTurn: '无回合',
+    round: '轮次',
+    attempt: '尝试',
+    updated: '更新',
+    output: '输出',
+    latestOutput: '最新输出',
+    outputHistory: '输出记录',
+    noOutput: '暂无输出',
+    recentMessages: '消息记录',
+    messageHistory: '消息记录',
+    noMessages: '暂无消息',
+    details: '详情',
+    message: 'Message',
+    messagePlaceholder: '输入请求...',
+    send: '发送',
+    sending: '发送中...',
+    error: '错误',
+    filterAll: '全部',
+    sortRecent: '最近活动',
+    sortName: '名称',
+    sortQueue: '队列大小',
+    sortLabel: '排序',
+  },
+  ja: {
+    empty: 'ルームなし。',
+    cardsAria: 'ルーム状態カード',
+    room: 'ルーム',
+    service: 'サービス',
+    agent: 'エージェント',
+    status: '状態',
+    queue: 'キュー',
+    queueWaitingMessages: '待機メッセージ',
+    tasks: 'タスク',
+    elapsed: '経過',
+    activity: '進行',
+    loadingActivity: '進行を読み込み中',
+    noActivity: '進行なし',
+    task: 'タスク',
+    noTask: 'タスクなし',
+    currentTurn: '現在ターン',
+    noTurn: 'ターンなし',
+    round: 'ラウンド',
+    attempt: '試行',
+    updated: '更新',
+    output: '出力',
+    latestOutput: '最新出力',
+    outputHistory: '出力履歴',
+    noOutput: '出力なし',
+    recentMessages: 'メッセージ履歴',
+    messageHistory: 'メッセージ履歴',
+    noMessages: 'メッセージなし',
+    details: '詳細',
+    message: 'メッセージ',
+    messagePlaceholder: '依頼を入力...',
+    send: '送信',
+    sending: '送信中...',
+    error: 'エラー',
+    filterAll: '全て',
+    sortRecent: '最近の活動',
+    sortName: '名前順',
+    sortQueue: 'キュー順',
+    sortLabel: '並び替え',
+  },
+} satisfies Record<Locale, RoomMessages>;
diff --git a/apps/dashboard/src/styles.css b/apps/dashboard/src/styles.css
index 0c41bc2..9f726b3 100644
--- a/apps/dashboard/src/styles.css
+++ b/apps/dashboard/src/styles.css
@@ -3004,35 +3004,66 @@ progress::-moz-progress-bar {
 
   .usage-row {
     grid-template-columns:
-      minmax(86px, 0.86fr) minmax(62px, 0.54fr) minmax(62px, 0.54fr)
-      minmax(58px, 0.4fr);
-    gap: 5px;
-    padding: 9px;
+      minmax(72px, 0.82fr) minmax(52px, 0.48fr) minmax(52px, 0.48fr)
+      minmax(48px, 0.36fr);
+    gap: 4px;
+    padding: 7px 6px;
   }
 
   .usage-account {
     display: grid;
-    gap: 5px;
+    gap: 3px;
+  }
+
+  .usage-account div {
+    gap: 3px;
+  }
+
+  .usage-account strong {
+    font-size: 13px;
+  }
+
+  .usage-account .pill,
+  .usage-account .mono-chip {
+    padding: 3px 6px;
+    font-size: 10px;
   }
 
   .usage-quota,
   .usage-speed {
-    gap: 4px;
+    gap: 3px;
   }
 
   .usage-quota {
-    padding: 5px;
+    padding: 4px;
   }
 
   .usage-quota div {
-    gap: 6px;
+    gap: 4px;
+  }
+
+  .usage-quota span,
+  .usage-speed span {
+    font-size: 9px;
+    letter-spacing: 0.04em;
+  }
+
+  .usage-quota strong,
+  .usage-speed strong {
+    font-size: 14px;
+  }
+
+  .usage-speed {
+    min-height: 0;
+    padding: 4px;
   }
 
   .usage-quota small {
-    overflow: hidden;
-    font-size: 10px;
-    text-overflow: ellipsis;
-    white-space: nowrap;
+    display: none;
+  }
+
+  .usage-speed small {
+    display: none;
   }
 
   .record-card-grid {
@@ -3168,7 +3199,7 @@ progress::-moz-progress-bar {
   }
 
   .usage-summary {
-    grid-template-columns: 1fr;
+    grid-template-columns: minmax(0, 1fr) auto;
   }
 
   .usage-summary div:last-child {
@@ -3176,19 +3207,19 @@ progress::-moz-progress-bar {
   }
 
   .usage-row {
-    grid-template-columns: minmax(0, 1fr) minmax(0, 1fr);
+    grid-template-columns:
+      minmax(68px, 0.8fr) minmax(48px, 0.48fr) minmax(48px, 0.48fr)
+      minmax(44px, 0.34fr);
   }
 
   .usage-account {
-    grid-column: 1 / -1;
+    grid-column: auto;
   }
 
   .usage-speed {
-    grid-column: 1 / -1;
-    display: flex;
-    min-height: auto;
-    align-items: center;
-    justify-content: space-between;
+    grid-column: auto;
+    display: grid;
+    min-height: 0;
   }
 
   .skeleton-grid,
@@ -4582,6 +4613,35 @@ progress::-moz-progress-bar {
   color: var(--muted);
 }
 
+@media (max-width: 640px) {
+  .usage-matrix {
+    overflow-x: hidden;
+  }
+
+  .usage-row {
+    grid-template-columns: minmax(0, 1fr) 62px 62px !important;
+    align-items: center;
+  }
+
+  .usage-speed {
+    display: none;
+  }
+
+  .usage-account strong {
+    font-size: 13px;
+  }
+
+  .usage-account .pill,
+  .usage-account .mono-chip {
+    padding: 3px 6px;
+    font-size: 10px;
+  }
+
+  .usage-quota {
+    min-width: 0;
+  }
+}
+
 @media (max-width: 760px) {
   .rooms-grid {
     grid-template-columns: 1fr;
diff --git a/apps/dashboard/src/useRoomActivity.ts b/apps/dashboard/src/useRoomActivity.ts
new file mode 100644
index 0000000..800df46
--- /dev/null
+++ b/apps/dashboard/src/useRoomActivity.ts
@@ -0,0 +1,68 @@
+import { useCallback, useEffect, useState } from 'react';
+
+import { fetchRoomTimeline, type DashboardRoomActivity } from './api';
+
+export type RoomActivityMap = Record<string, DashboardRoomActivity>;
+
+interface UseSelectedRoomActivityOptions {
+  active: boolean;
+  pollMs?: number;
+  selectedRoomJid: string | null;
+}
+
+export function useSelectedRoomActivity({
+  active,
+  pollMs = 2000,
+  selectedRoomJid,
+}: UseSelectedRoomActivityOptions): {
+  refreshRoom: (roomJid: string) => Promise<DashboardRoomActivity>;
+  roomActivity: RoomActivityMap;
+  roomActivityLoading: boolean;
+} {
+  const [roomActivity, setRoomActivity] = useState<RoomActivityMap>({});
+  const [roomActivityLoading, setRoomActivityLoading] = useState(false);
+
+  const refreshRoom = useCallback(async (roomJid: string) => {
+    const activity = await fetchRoomTimeline(roomJid);
+    setRoomActivity((previous) => ({
+      ...previous,
+      [roomJid]: activity,
+    }));
+    return activity;
+  }, []);
+
+  useEffect(() => {
+    if (!active || !selectedRoomJid) {
+      setRoomActivityLoading(false);
+      return undefined;
+    }
+
+    let cancelled = false;
+    let inFlight = false;
+    let pollIntervalId: number | null = null;
+
+    const fetchOnce = async (initial: boolean) => {
+      if (cancelled || inFlight) return;
+      inFlight = true;
+      if (initial) setRoomActivityLoading(true);
+      try {
+        await refreshRoom(selectedRoomJid);
+      } catch {
+        /* Keep the last good timeline snapshot. */
+      } finally {
+        inFlight = false;
+        if (!cancelled && initial) setRoomActivityLoading(false);
+      }
+    };
+
+    void fetchOnce(true);
+    pollIntervalId = window.setInterval(() => void fetchOnce(false), pollMs);
+
+    return () => {
+      cancelled = true;
+      if (pollIntervalId !== null) window.clearInterval(pollIntervalId);
+    };
+  }, [active, pollMs, refreshRoom, selectedRoomJid]);
+
+  return { refreshRoom, roomActivity, roomActivityLoading };
+}