diff --git a/apps/hq-web/src/app.css b/apps/hq-web/src/app.css
index 18ce189..5d313d6 100644
--- a/apps/hq-web/src/app.css
+++ b/apps/hq-web/src/app.css
@@ -153,6 +153,18 @@
 .wf-pager { display: flex; align-items: center; gap: 10px; margin-top: 10px; flex-wrap: wrap; font-size: 13px; color: var(--text-dim); }
 .wf-pager > span:first-child { margin-right: auto; }
 
+/* Per-module collapsible section on Client 360 → Modules: coloured header, everything of
+   one module lives inside it, so a client with many modules stays scannable. */
+.mod-section { border: 1px solid var(--border); border-radius: var(--radius); margin-top: 12px; overflow: hidden; background: var(--bg-raised); }
+.mod-section > summary { list-style: none; cursor: pointer; display: flex; align-items: center; gap: 10px;
+  padding: 10px 14px; background: var(--accent-soft); color: var(--accent-strong); font-weight: 700;
+  border-left: 4px solid var(--accent); user-select: none; }
+.mod-section > summary::-webkit-details-marker { display: none; }
+.mod-section > summary::before { content: '▸'; font-size: 12px; transition: transform .15s ease; opacity: .8; }
+.mod-section[open] > summary::before { transform: rotate(90deg); }
+.mod-section > summary .mod-name { flex: 1; font-size: 14px; letter-spacing: .2px; }
+.mod-section-body { padding: 10px 14px 14px; }
+
 /* Section header shared by the queue block and the bento cards */
 .dash-head { display: flex; align-items: center; gap: 10px; padding: 2px 0 10px; }
 .dash-head h3 { font-size: 12px; font-weight: 700; text-transform: uppercase; letter-spacing: 0.07em; color: var(--text-dim); margin: 0; }
diff --git a/apps/hq-web/src/pages/ClientDetail.tsx b/apps/hq-web/src/pages/ClientDetail.tsx
index 8d0df8c..a9bf323 100644
--- a/apps/hq-web/src/pages/ClientDetail.tsx
+++ b/apps/hq-web/src/pages/ClientDetail.tsx
@@ -293,17 +293,26 @@ export function ClientDetail() {
                 })}
               />
             )}
-          {(cms.data ?? []).length > 0 && <h3 style={{ marginTop: 20 }}>Service data</h3>}
+          {(cms.data ?? []).length > 0 && <h3 style={{ marginTop: 20 }}>Service details by module</h3>}
           {(cms.data ?? []).map((cm) => (
-            <Fragment key={cm.id}>
-              <ServiceDataCard
-                cm={cm}
-                name={moduleName(cm.moduleId)}
-                fieldSpec={modules.data?.find((m) => m.id === cm.moduleId)?.fieldSpec ?? []}
-                onChanged={() => cms.reload()}
-              />
-              <MilestoneChecklist clientModuleId={cm.id} name={moduleName(cm.moduleId)} />
-            </Fragment>
+            // Everything of one module (service data + onboarding checklist) sits inside its
+            // own coloured, collapsible section — a client with many modules stays scannable.
+            <details key={cm.id} open className="mod-section">
+              <summary>
+                <span className="mod-name">{moduleName(cm.moduleId)}</span>
+                <Badge tone={cm.status === 'live' ? 'ok' : undefined}>{cm.status}</Badge>
+                <Badge>{KIND_LABEL[cm.kind]}</Badge>
+              </summary>
+              <div className="mod-section-body">
+                <ServiceDataCard
+                  cm={cm}
+                  name={moduleName(cm.moduleId)}
+                  fieldSpec={modules.data?.find((m) => m.id === cm.moduleId)?.fieldSpec ?? []}
+                  onChanged={() => cms.reload()}
+                />
+                <MilestoneChecklist clientModuleId={cm.id} name={moduleName(cm.moduleId)} />
+              </div>
+            </details>
           ))}
         </>
       )}