Fix arrow edge color.

lynxkite-app/web/src/index.css

@@ -322,11 +322,6 @@ body {
   }
 }
 
-path.react-flow__edge-path {
-  stroke-width: 2;
-  stroke: black;
-}
-
 .react-flow__edge.selected path.react-flow__edge-path {
   outline: var(--xy-selection-border, var(--xy-selection-border-default));
   outline-offset: 10px;

lynxkite-app/web/src/workspace/Workspace.tsx

@@ -282,7 +282,18 @@ function LynxKiteFlow() {
             proOptions={{ hideAttribution: true }}
             maxZoom={3}
             minZoom={0.3}
-            defaultEdgeOptions={{ markerEnd: { type: MarkerType.Arrow } }}
+            defaultEdgeOptions={{
+              markerEnd: {
+                type: MarkerType.ArrowClosed,
+                color: "black",
+                width: 15,
+                height: 15,
+              },
+              style: {
+                strokeWidth: 2,
+                stroke: "black",
+              },
+            }}
           >
             <Controls />
             <MiniMap />