diff --git a/src/mes/operationGuide/component/FlowChart.js b/src/mes/operationGuide/component/FlowChart.js
index 5e5791e..daeaf5e 100644
--- a/src/mes/operationGuide/component/FlowChart.js
+++ b/src/mes/operationGuide/component/FlowChart.js
@@ -335,7 +335,7 @@ const BroadsideCardRender = (props) => {
 
         const graph = new window.X6.Graph({
             container:document.getElementById('container'),
-            width: document.querySelector('#flowBody').offsetWidth,
+            width: document.querySelector('#flowBody')?.offsetWidth,
             height: document.querySelector('#flowBody').offsetHeight
         });