diff --git a/example/lib/main.dart b/example/lib/main.dart
index eafa53c..8adc4c8 100644
--- a/example/lib/main.dart
+++ b/example/lib/main.dart
@@ -39,8 +39,9 @@ class _TestScreenState extends State<TestScreen> {
       MindMapData(
         id: 'node1',
         title: '📝 노드1',
+        borderColor: Colors.green,
         children: [
-          MindMapData(id: 'sub1', title: '서브1'),
+          MindMapData(id: 'sub1', title: '서브1', borderColor: Colors.purple),
           MindMapData(id: 'sub2', title: '서브2'),
         ],
       ),
@@ -94,6 +95,9 @@ class _TestScreenState extends State<TestScreen> {
                   '🍃 첫리프',
                   () => _focusToNode(CameraFocus.firstLeaf, null),
                 ),
+                // Forward/Backward focus buttons
+                _buildButton('⬅️ 이전', _focusPreviousNode),
+                _buildButton('다음 ➡️', _focusNextNode),
               ],
             ),
           ),
@@ -171,7 +175,7 @@ class _TestScreenState extends State<TestScreen> {
                     levelSpacing: 120,
                     nodeMargin: 15,
                   ),
-                  cameraFocus: CameraFocus.fitAll,
+                  cameraFocus: currentFocus,
                   focusNodeId: targetNodeId,
                   focusAnimation: const Duration(
                     milliseconds: 1000,
@@ -256,4 +260,31 @@ class _TestScreenState extends State<TestScreen> {
         return '🌳 전체트리';
     }
   }
+
+  void _focusNextNode() {
+    final flatNodes = mindMapData.flatten();
+    if (flatNodes.isEmpty) return;
+    int currentIdx = flatNodes.indexWhere((n) => n.id == targetNodeId);
+    int nextIdx = (currentIdx + 1) % flatNodes.length;
+    final nextNode = flatNodes[nextIdx];
+    setState(() {
+      currentFocus = CameraFocus.custom;
+      targetNodeId = nextNode.id;
+      lastAction = '다음 노드로 이동: ${nextNode.title}';
+    });
+  }
+
+  void _focusPreviousNode() {
+    final flatNodes = mindMapData.flatten();
+    if (flatNodes.isEmpty) return;
+    int currentIdx = flatNodes.indexWhere((n) => n.id == targetNodeId);
+    int prevIdx = (currentIdx - 1);
+    if (prevIdx < 0) prevIdx = flatNodes.length - 1;
+    final prevNode = flatNodes[prevIdx];
+    setState(() {
+      currentFocus = CameraFocus.custom;
+      targetNodeId = prevNode.id;
+      lastAction = '이전 노드로 이동: ${prevNode.title}';
+    });
+  }
 }
diff --git a/lib/src/models/mind_map_data.dart b/lib/src/models/mind_map_data.dart
index 20985d6..ccb45bb 100644
--- a/lib/src/models/mind_map_data.dart
+++ b/lib/src/models/mind_map_data.dart
@@ -107,6 +107,15 @@ class MindMapData {
 
   @override
   String toString() {
-    return 'MindMapData(id: $id, title: $title, children: ${children.length})';
+    return 'MindMapData(id: $id, title: $title, children:  [36m${children.length} [0m)';
+  }
+
+  /// Returns a flat list of all nodes in pre-order traversal (self, then children)
+  List<MindMapData> flatten() {
+    List<MindMapData> result = [this];
+    for (final child in children) {
+      result.addAll(child.flatten());
+    }
+    return result;
   }
 }
diff --git a/lib/src/widgets/mind_map_widget.dart b/lib/src/widgets/mind_map_widget.dart
index 7c7ae90..0ef3a72 100644
--- a/lib/src/widgets/mind_map_widget.dart
+++ b/lib/src/widgets/mind_map_widget.dart
@@ -1,13 +1,14 @@
+import 'dart:math' as math;
+
 import 'package:flutter/material.dart';
 import 'package:flutter/services.dart';
-import 'dart:math' as math;
 
-import '../models/mind_map_data.dart';
-import '../models/mind_map_style.dart';
-import '../models/mind_map_node.dart';
+import '../enums/camera_focus.dart';
 import '../enums/mind_map_layout.dart';
 import '../enums/node_shape.dart';
-import '../enums/camera_focus.dart';
+import '../models/mind_map_data.dart';
+import '../models/mind_map_node.dart';
+import '../models/mind_map_style.dart';
 // import '../enums/mind_map_type.dart';
 import '../painters/mind_map_painter.dart';
 import '../painters/node_painter.dart';
@@ -1647,6 +1648,8 @@ class _MindMapWidgetState extends State<MindMapWidget>
   /// 개별 노드 위젯 빌드 / Build individual node widget
   Widget _buildNodeWidget(MindMapNode node) {
     final isSelected = _selectedNodeId == node.id;
+    final isFocused =
+        widget.focusNodeId != null && widget.focusNodeId == node.id;
 
     final actualSize = widget.style.getActualNodeSize(
       node.title,
@@ -1746,8 +1749,11 @@ class _MindMapWidgetState extends State<MindMapWidget>
     final nodeColor = node.color;
     final textColor = node.textColor ?? widget.style.defaultTextStyle.color;
     final borderColor =
-        node.borderColor ??
-        (isSelected ? widget.style.selectionBorderColor : Colors.white);
+        (isFocused || isSelected)
+            ? widget.style.selectionBorderColor
+            : (node.borderColor ?? Colors.white);
+    final borderWidth =
+        (isFocused || isSelected) ? widget.style.selectionBorderWidth : 2.0;
 
     return Positioned(
       key: ValueKey('positioned_${node.id}'),
@@ -1785,8 +1791,7 @@ class _MindMapWidgetState extends State<MindMapWidget>
                 shape: widget.style.nodeShape,
                 fillColor: nodeColor,
                 borderColor: borderColor,
-                borderWidth:
-                    isSelected ? widget.style.selectionBorderWidth : 2.0,
+                borderWidth: borderWidth,
                 shadowEnabled: widget.style.enableNodeShadow,
                 shadowColor: widget.style.nodeShadowColor,
                 shadowBlurRadius: widget.style.nodeShadowBlurRadius,