style(App.css): add overflow: hidden to body to prevent horizontal scrolling

style(App.css): remove unnecessary auto values for width, height, and border-radius in .react-flow__node class

src/frontend/src/App.css

@@ -2,6 +2,10 @@
 @tailwind components;
 @tailwind utilities;
 
+body {
+  overflow: hidden;
+}
+
 .App {
   text-align: center;
 }