diff --git a/web/hwlab-cloud-web/scripts/agent-observer-ui-contract.test.ts b/web/hwlab-cloud-web/scripts/agent-observer-ui-contract.test.ts
index 360931cd..120e5a62 100644
--- a/web/hwlab-cloud-web/scripts/agent-observer-ui-contract.test.ts
+++ b/web/hwlab-cloud-web/scripts/agent-observer-ui-contract.test.ts
@@ -82,6 +82,7 @@ test("AgentRun command bar preserves compact desktop and mobile primary controls
 });
 
 test("AgentRun workspace always owns the remaining grid row", () => {
+  assert.match(styleSource, /agent-observer-page \{[\s\S]*?height: 100%;/);
   assert.match(styleSource, /agent-observer-workspace \{ grid-row: -2 \/ -1;/);
 });
 
diff --git a/web/hwlab-cloud-web/src/styles/agent-observer.css b/web/hwlab-cloud-web/src/styles/agent-observer.css
index db308cc7..9228bbd2 100644
--- a/web/hwlab-cloud-web/src/styles/agent-observer.css
+++ b/web/hwlab-cloud-web/src/styles/agent-observer.css
@@ -1,7 +1,7 @@
 .agent-observer-page {
   width: 100%;
   max-width: 100%;
-  height: calc(100dvh - var(--platform-topbar-height, 56px));
+  height: 100%;
   min-width: 0;
   min-height: 0;
   display: grid;