diff --git a/miniapp/pages/index/index.js b/miniapp/pages/index/index.js
index 19385d2..d86cc20 100644
--- a/miniapp/pages/index/index.js
+++ b/miniapp/pages/index/index.js
@@ -496,6 +496,23 @@ function buildSankeyLayout(links, width, height, renderOptions) {
     }
   }
 
+  // 与 Web 端 nodeAlign='justify' 对齐：
+  // - 无入边节点固定在最左列
+  // - 无出边节点固定在最右列
+  // 这样可避免“短路径末端节点停在中间列”的视觉差异。
+  const baseMaxDepth = nodeNames.reduce((max, name) => Math.max(max, depthMap[name] || 0), 0);
+  nodeNames.forEach((name) => {
+    const incomingCount = incomingCountMap[name] || 0;
+    const outgoingCount = outgoingCountMap[name] || 0;
+    if (incomingCount === 0 && outgoingCount > 0) {
+      depthMap[name] = 0;
+      return;
+    }
+    if (outgoingCount === 0 && incomingCount > 0) {
+      depthMap[name] = baseMaxDepth;
+    }
+  });
+
   const maxDepth = nodeNames.reduce((max, name) => Math.max(max, depthMap[name] || 0), 0);
   const columns = Array.from({ length: maxDepth + 1 }, () => []);
   nodeNames.forEach((name) => {
@@ -591,7 +608,9 @@ function buildSankeyLayout(links, width, height, renderOptions) {
         x: nodeX,
         y: cursorY,
         h: nodeHeight,
-        colorIndex: Number.isFinite(nodeColorIndexMap[name]) ? nodeColorIndexMap[name] : 0
+        colorIndex: Number.isFinite(nodeColorIndexMap[name]) ? nodeColorIndexMap[name] : 0,
+        incomingCount: incomingCountMap[name] || 0,
+        outgoingCount: outgoingCountMap[name] || 0
       };
       nodes.push(node);
       nodePositionMap[name] = node;
@@ -696,8 +715,8 @@ function buildSankeySvgText(links, width, height, renderOptions) {
   });
 
   layout.nodes.forEach((node) => {
-    const isSource = node.depth === 0;
-    const isTarget = node.depth === layout.maxDepth;
+    const isSource = node.incomingCount === 0 && node.outgoingCount > 0;
+    const isTarget = node.outgoingCount === 0 && node.incomingCount > 0;
     const textY = getClampedLabelY(
       node.y,
       node.h,
@@ -1407,8 +1426,8 @@ Page({
       });
 
       layout.nodes.forEach((node) => {
-        const isSource = node.depth === 0;
-        const isTarget = node.depth === layout.maxDepth;
+        const isSource = node.incomingCount === 0 && node.outgoingCount > 0;
+        const isTarget = node.outgoingCount === 0 && node.incomingCount > 0;
         const labelPlacement = getCanvasLabelPlacement(
           node.x,
           layout.nodeWidth,