diff --git a/web/hwlab-cloud-web/src/state/issue853-refresh-regression.test.ts b/web/hwlab-cloud-web/src/state/issue853-refresh-regression.test.ts
index cd6e9d70..fe6a0a65 100644
--- a/web/hwlab-cloud-web/src/state/issue853-refresh-regression.test.ts
+++ b/web/hwlab-cloud-web/src/state/issue853-refresh-regression.test.ts
@@ -34,6 +34,9 @@ test("issue 853 left sidebar collapse only removes the left columns", () => {
   const css = fs.readFileSync(path.join(srcRoot, "styles/workbench.css"), "utf8");
   assert.match(css, /--right-sidebar-left-collapsed-width: min\(var\(--right-sidebar-width\), 46vw\);/u);
   assert.match(css, /\.workbench-shell\.is-left-sidebar-collapsed \.workspace-body \{ grid-template-columns: 0 0 minmax\(360px, 1fr\) var\(--resize-handle-width\) minmax\(min\(var\(--right-sidebar-min-width\), 46vw\), var\(--right-sidebar-left-collapsed-width\)\); \}/u);
+  assert.match(css, /\.center-workspace \{ grid-column: 3; \}/u);
+  assert.match(css, /\.right-sidebar \{ grid-column: 5; \}/u);
+  assert.match(css, /\.workspace-body\.is-route-without-sidebars \.center-workspace \{ grid-column: 1; \}/u);
   assert.doesNotMatch(css, /\.workbench-shell\.is-left-sidebar-collapsed \.workspace-body \{ grid-template-columns: 0 0 minmax\(0, 1fr\) var\(--resize-handle-width\) var\(--right-sidebar-width\); \}/u);
 });
 
diff --git a/web/hwlab-cloud-web/src/styles/workbench.css b/web/hwlab-cloud-web/src/styles/workbench.css
index 8f932f8e..1318e425 100644
--- a/web/hwlab-cloud-web/src/styles/workbench.css
+++ b/web/hwlab-cloud-web/src/styles/workbench.css
@@ -60,6 +60,12 @@ button:disabled { cursor: not-allowed; opacity: 0.55; }
 .workbench-shell.is-right-sidebar-collapsed .workspace-body { grid-template-columns: var(--session-sidebar-width) var(--resize-handle-width) minmax(420px, 1fr) 0 0; }
 .workbench-shell.is-left-sidebar-collapsed.is-right-sidebar-collapsed .workspace-body { grid-template-columns: 0 0 minmax(0, 1fr) 0 0; }
 .workspace-body.is-route-without-sidebars { grid-template-columns: minmax(0, 1fr); }
+.session-sidebar { grid-column: 1; }
+.session-sidebar-resize { grid-column: 2; }
+.center-workspace { grid-column: 3; }
+.right-sidebar-resize { grid-column: 4; }
+.right-sidebar { grid-column: 5; }
+.workspace-body.is-route-without-sidebars .center-workspace { grid-column: 1; }
 .activity-rail { min-width: 0; display: grid; grid-template-rows: repeat(5, minmax(54px, auto)) 1fr minmax(54px, auto); gap: 6px; padding: 10px 8px; background: var(--rail); overflow-x: hidden; }
 .rail-button { min-width: 0; min-height: 44px; border: 1px solid rgba(255,255,255,0.12); border-radius: 6px; padding: 8px 6px; background: transparent; color: #eef4ed; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
 .rail-button.active { color: #1d2b23; background: var(--rail-active); border-color: var(--rail-active); }