diff --git a/langfun/core/eval/v2/evaluation.py b/langfun/core/eval/v2/evaluation.py
index 3883770..3a3fb96 100644
--- a/langfun/core/eval/v2/evaluation.py
+++ b/langfun/core/eval/v2/evaluation.py
@@ -556,6 +556,9 @@ def _html_tree_view_css_styles(self) -> list[str]:
           border: 0px;
           margin: 0px;
         }
+        .eval-details .tab-control {
+          width: 100%;
+        }
         .eval-details .tab-button {
           font-size: large;
         }