Fix rounded corners on boxes.

lynxkite-app/web/src/index.css

@@ -76,6 +76,7 @@ body {
   .lynxkite-node {
     box-shadow: 0px 5px 50px 0px rgba(0, 0, 0, 0.3);
     border-radius: 4px;
+    overflow: hidden;
     background: white;
     display: flex;
     flex-direction: column;