diff --git a/src/pages/agent-office/AgentOffice.css b/src/pages/agent-office/AgentOffice.css
index 8cfa59a..71df0f6 100644
--- a/src/pages/agent-office/AgentOffice.css
+++ b/src/pages/agent-office/AgentOffice.css
@@ -447,3 +447,50 @@
     padding-bottom: env(safe-area-inset-bottom, 16px);
   }
 }
+
+/* ── 횡단 오버사이트 타임라인 ── */
+.ao-activity { display: flex; flex-direction: column; min-height: 0; }
+.ao-activity-header { display: flex; align-items: center; }
+
+.ao-activity-filters {
+  display: flex; flex-wrap: wrap; gap: 6px;
+  padding: 8px 12px; border-bottom: 1px solid #1f2937;
+}
+.ao-activity-select {
+  background: #111827; color: #e5e7eb;
+  border: 1px solid #374151; border-radius: 6px;
+  padding: 4px 8px; font-size: 12px;
+}
+.ao-activity-select:disabled { opacity: .4; cursor: not-allowed; }
+
+.ao-activity-content { flex: 1; overflow-y: auto; min-height: 0; }
+
+.ao-activity-item {
+  display: flex; align-items: flex-start; gap: 10px;
+  padding: 10px 12px; border-bottom: 1px solid #161b25;
+  cursor: pointer; transition: background .12s;
+}
+.ao-activity-item:hover { background: #161b25; }
+.ao-activity-item.is-highlight { background: rgba(245, 158, 11, .08); }
+.ao-activity-dot { flex: 0 0 auto; width: 8px; height: 8px; border-radius: 50%; margin-top: 5px; }
+.ao-activity-body { flex: 1; min-width: 0; }
+.ao-activity-line { display: flex; align-items: center; gap: 8px; }
+.ao-activity-agent { font-size: 12px; font-weight: 600; }
+.ao-activity-badge { font-size: 11px; padding: 1px 7px; border-radius: 10px; white-space: nowrap; }
+.ao-activity-level { font-size: 12px; }
+.ao-activity-msg {
+  font-size: 13px; color: #cbd5e1; margin-top: 2px;
+  overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
+}
+.ao-activity-meta { flex: 0 0 auto; display: flex; flex-direction: column; align-items: flex-end; gap: 2px; }
+.ao-activity-time { font-size: 11px; color: #6b7280; }
+.ao-activity-dur { font-size: 10px; color: #475569; }
+
+.ao-activity-loading,
+.ao-activity-end { text-align: center; padding: 12px; font-size: 12px; color: #6b7280; }
+.ao-activity-sentinel { height: 1px; }
+.ao-activity-error { padding: 12px; font-size: 13px; color: #fca5a5; }
+.ao-activity-error button {
+  margin-left: 8px; background: #374151; color: #e5e7eb;
+  border: none; border-radius: 6px; padding: 2px 10px; cursor: pointer;
+}