diff --git a/res/css/structures/_LeftPanel.scss b/res/css/structures/_LeftPanel.scss
index 7d57425f6f..35d9f0e7da 100644
--- a/res/css/structures/_LeftPanel.scss
+++ b/res/css/structures/_LeftPanel.scss
@@ -19,6 +19,7 @@ limitations under the License.
     display: flex;
     /* LeftPanel 260px */
     min-width: 260px;
+    max-width: 50%;
     flex: 0 0 auto;
 }
 
diff --git a/res/css/structures/_RightPanel.scss b/res/css/structures/_RightPanel.scss
index 10878322e3..22b37cebfa 100644
--- a/res/css/structures/_RightPanel.scss
+++ b/res/css/structures/_RightPanel.scss
@@ -20,6 +20,7 @@ limitations under the License.
     flex: 0 0 auto;
     position: relative;
     min-width: 264px;
+    max-width: 50%;
     display: flex;
     flex-direction: column;
 }