diff --git a/bandwidth-test.bin b/bandwidth-test.bin
new file mode 100644
index 0000000..d9d1204
Binary files /dev/null and b/bandwidth-test.bin differ
diff --git a/build_output.txt b/build_output.txt
index 0f5c296..c62ca6e 100644
--- a/build_output.txt
+++ b/build_output.txt
@@ -2,8 +2,8 @@
 
   Checking File Globs
   godot-cpp.vcxproj -> E:\newgame\marry\build\bin\libgodot-cpp.windows.template_debug.x86_64.lib
-  pingpong_ball.cpp
+  register_types.cpp
+  pingpong_game.cpp
     正在创建库 E:/newgame/marry/main/bin/Release/pingpang.lib 和对象 E:/newgame/marry/main/bin/Release/pingpang.exp
   pingpang.vcxproj -> E:\newgame\marry\main\bin\Release\pingpang.dll
   复制 pingpang.dll 到 main/bin/ 根目录
-  Building Custom Rule E:/newgame/marry/CMakeLists.txt
diff --git a/main/scenes/main.tscn b/main/scenes/main.tscn
index 1aff08a..9561a8d 100644
--- a/main/scenes/main.tscn
+++ b/main/scenes/main.tscn
@@ -1,15 +1,16 @@
 [gd_scene load_steps=4 format=3]
 
 [sub_resource type="CircleShape2D" id="circle_ball"]
-radius = 12.0
+radius = 10.0
 
 [sub_resource type="RectangleShape2D" id="rect_paddle"]
-size = Vector2(20.0, 120.0)
+size = Vector2(18.0, 100.0)
 
 [node name="Game" type="PingPongGame"]
 
 [node name="Ball" type="PingPongBall" parent="Game"]
 position = Vector2(576.0, 324.0)
+initial_speed = 350.0
 
 [node name="CollisionShape2D" type="CollisionShape2D" parent="Game/Ball"]
 shape = SubResource("circle_ball")
@@ -51,9 +52,17 @@ horizontal_alignment = 1
 theme_override_font_sizes/font_size = 48
 theme_override_colors/font_color = Color(1.0, 1.0, 1.0, 1.0)
 
-[node name="CenterLine" type="ColorRect" parent="Game/UI"]
-offset_left = 574.0
-offset_top = 0.0
-offset_right = 578.0
-offset_bottom = 648.0
-color = Color(1.0, 1.0, 1.0, 0.1)
+[node name="Message" type="Label" parent="Game/UI"]
+anchor_left = 0.5
+anchor_top = 0.5
+anchor_right = 0.5
+anchor_bottom = 0.5
+offset_left = -200.0
+offset_top = -100.0
+offset_right = 200.0
+offset_bottom = 100.0
+text = "按空格键开始"
+horizontal_alignment = 1
+vertical_alignment = 1
+theme_override_font_sizes/font_size = 36
+theme_override_colors/font_color = Color(1.0, 1.0, 1.0, 0.9)
diff --git a/src/pingpong_ball.cpp b/src/pingpong_ball.cpp
index 24050a5..dd71acd 100644
--- a/src/pingpong_ball.cpp
+++ b/src/pingpong_ball.cpp
@@ -11,12 +11,24 @@
 
 using namespace godot;
 
+// ═══════════════════════════════════════════════════════
+// 视觉颜色常量 — 以后替换素材时删除本段
+// ═══════════════════════════════════════════════════════
+static const Color BALL_COLOR = Color(1.0f, 1.0f, 1.0f);
+
 void PingPongBall::_bind_methods() {
     // 属性
     ClassDB::bind_method(D_METHOD("get_speed"), &PingPongBall::get_speed);
     ClassDB::bind_method(D_METHOD("set_speed", "value"), &PingPongBall::set_speed);
     ClassDB::add_property("PingPongBall", PropertyInfo(Variant::FLOAT, "speed"), "set_speed", "get_speed");
 
+    ClassDB::bind_method(D_METHOD("get_initial_speed"), &PingPongBall::get_initial_speed);
+    ClassDB::bind_method(D_METHOD("set_initial_speed", "value"), &PingPongBall::set_initial_speed);
+    ClassDB::add_property("PingPongBall", PropertyInfo(Variant::FLOAT, "initial_speed"), "set_initial_speed", "get_initial_speed");
+
+    ClassDB::bind_method(D_METHOD("get_active"), &PingPongBall::get_active);
+    ClassDB::bind_method(D_METHOD("set_active", "value"), &PingPongBall::set_active);
+
     // 方法
     ClassDB::bind_method(D_METHOD("reset"), &PingPongBall::reset);
 
@@ -25,7 +37,9 @@ void PingPongBall::_bind_methods() {
 }
 
 PingPongBall::PingPongBall() {
-    speed = 400.0f;
+    speed = 350.0f;
+    initial_speed = 350.0f;
+    is_active = false;
 }
 
 PingPongBall::~PingPongBall() {
@@ -35,78 +49,98 @@ void PingPongBall::_ready() {
     reset();
 }
 
+// ═══════════════════════════════════════════════════════
+// 视觉层 — 球体 + 拖尾（几何体占位）
+// 替换方法：删除本方法 → 添加 Sprite2D 子节点
+// ═══════════════════════════════════════════════════════
 void PingPongBall::_draw() {
-    // 画一个白色圆形表示球
-    draw_circle(Vector2(0.0f, 0.0f), 12.0f, Color(1.0f, 1.0f, 1.0f));
+    // 拖尾：从旧到新画渐隐圆
+    int trail_count = (int)trail_positions.size();
+    for (int i = 0; i < trail_count; i++) {
+        float alpha = (float)(i + 1) / (float)BALL_TRAIL_LENGTH * 0.3f;
+        float radius = BALL_RADIUS * (0.5f + 0.5f * (float)(i + 1) / (float)BALL_TRAIL_LENGTH);
+        draw_circle(trail_positions[i], radius, Color(1.0f, 1.0f, 1.0f, alpha));
+    }
+
+    // 球本体
+    draw_circle(Vector2(0.0f, 0.0f), BALL_RADIUS, BALL_COLOR);
 }
 
 void PingPongBall::_physics_process(double delta) {
     queue_redraw();
+
+    if (!is_active) {
+        return;
+    }
+
+    // 更新拖尾
+    trail_positions.push_back(get_position());
+    if ((int)trail_positions.size() > BALL_TRAIL_LENGTH) {
+        trail_positions.erase(trail_positions.begin());
+    }
+
     Vector2 velocity = direction * speed * (float)delta;
 
     Ref<KinematicCollision2D> collision = move_and_collide(velocity);
 
     if (collision.is_valid()) {
-        // 计算反弹方向
         Vector2 normal = collision->get_normal();
         direction = direction.bounce(normal);
 
-        // 根据碰撞法线判断碰撞对象类型
-        // 法线主要水平 → 碰到球拍（左右反弹）
-        // 法线主要垂直 → 碰到上下墙（上下反弹）
-        // 如果法线接近水平且球已经接近左右边界 → 得分
         Object *collider = collision->get_collider();
         if (collider) {
             Node *collider_node = Object::cast_to<Node>(collider);
             if (collider_node) {
                 StringName node_name = collider_node->get_name();
-                // 判断是不是球拍（球拍名字包含 "Paddle"）
+                // 碰到球拍
                 if (node_name.find("Paddle") != -1) {
-                    // 碰到球拍，微调角度（根据击中位置）
                     Node2D *collider_2d = Object::cast_to<Node2D>(collider_node);
                     if (collider_2d) {
+                        // 根据击中位置微调角度
                         float hit_offset = (get_global_position().y - collider_2d->get_global_position().y) / 60.0f;
                         hit_offset = CLAMP(hit_offset, -1.0f, 1.0f);
                         direction.y += hit_offset * 0.5f;
                         direction = direction.normalized();
+
+                        // 速度递增
+                        speed *= BALL_SPEED_INCREMENT;
+                        if (speed > BALL_MAX_SPEED) {
+                            speed = BALL_MAX_SPEED;
+                        }
                     }
                 }
             }
         }
 
-        // 确保方向始终有效
         direction = direction.normalized();
     }
 
-    // 检测是否出界（得分判定）
+    // 得分判定
     Viewport *viewport = get_viewport();
     if (viewport) {
         Vector2 screen_size = viewport->get_visible_rect().size;
         Vector2 pos = get_global_position();
 
         if (pos.x < -50.0f) {
-            // 球从左边出界，右边得分
             emit_signal("scored", 1);
             reset();
         } else if (pos.x > screen_size.x + 50.0f) {
-            // 球从右边出界，左边得分
             emit_signal("scored", 0);
             reset();
         }
 
-        // Y 方向边界限制（防止飞出屏幕）
-        if (pos.y < 0.0f) {
-            set_global_position(Vector2(pos.x, 0.0f));
+        // Y 边界限制
+        if (pos.y < BALL_RADIUS) {
+            set_global_position(Vector2(pos.x, BALL_RADIUS));
             direction.y = std::abs(direction.y);
-        } else if (pos.y > screen_size.y) {
-            set_global_position(Vector2(pos.x, screen_size.y));
+        } else if (pos.y > screen_size.y - BALL_RADIUS) {
+            set_global_position(Vector2(pos.x, screen_size.y - BALL_RADIUS));
             direction.y = -std::abs(direction.y);
         }
     }
 }
 
 void PingPongBall::reset() {
-    // 回到屏幕中央
     Viewport *viewport = get_viewport();
     if (viewport) {
         Vector2 screen_size = viewport->get_visible_rect().size;
@@ -115,18 +149,32 @@ void PingPongBall::reset() {
         set_global_position(Vector2(640.0f, 360.0f));
     }
 
-    // 随机方向（-45° 到 45° 之间，向左或向右随机）
-    float angle = (UtilityFunctions::randf() - 0.5f) * Math_PI / 2.0f;  // -45° ~ 45°
+    // 重置速度
+    speed = initial_speed;
+
+    // 清空拖尾
+    trail_positions.clear();
+
+    // 随机方向
+    float angle = (UtilityFunctions::randf() - 0.5f) * Math_PI / 2.0f;
     int side = (UtilityFunctions::randf() > 0.5f) ? 1 : -1;
     direction = Vector2((float)side * std::cos(angle), std::sin(angle)).normalized();
 
-    // 确保水平分量足够（避免球过于垂直）
+    // 确保水平分量足够
     if (std::abs(direction.x) < 0.3f) {
         direction.x = (direction.x > 0 ? 1.0f : -1.0f) * 0.3f;
         direction = direction.normalized();
     }
 }
 
+void PingPongBall::set_active(bool p_active) {
+    is_active = p_active;
+}
+
+bool PingPongBall::get_active() const {
+    return is_active;
+}
+
 void PingPongBall::set_speed(float p_speed) {
     speed = p_speed;
 }
@@ -134,3 +182,11 @@ void PingPongBall::set_speed(float p_speed) {
 float PingPongBall::get_speed() const {
     return speed;
 }
+
+void PingPongBall::set_initial_speed(float p_speed) {
+    initial_speed = p_speed;
+}
+
+float PingPongBall::get_initial_speed() const {
+    return initial_speed;
+}
diff --git a/src/pingpong_ball.h b/src/pingpong_ball.h
index bde96c4..03dbd5a 100644
--- a/src/pingpong_ball.h
+++ b/src/pingpong_ball.h
@@ -2,15 +2,30 @@
 #define PINGPONG_BALL_H
 
 #include <godot_cpp/classes/character_body2d.hpp>
+#include <vector>
 
 namespace godot {
 
+// ═══════════════════════════════════════════════════════
+// 视觉常量 — 以后替换为 Sprite2D 时删除本段
+// (颜色值定义在 pingpong_ball.cpp 中)
+// ═══════════════════════════════════════════════════════
+static constexpr int BALL_TRAIL_LENGTH = 8;
+static constexpr float BALL_RADIUS = 10.0f;
+static constexpr float BALL_SPEED_INCREMENT = 1.03f;
+static constexpr float BALL_MAX_SPEED = 800.0f;
+
 class PingPongBall : public CharacterBody2D {
     GDCLASS(PingPongBall, CharacterBody2D)
 
 private:
-    float speed = 300.0f;
+    float speed = 350.0f;
+    float initial_speed = 350.0f;
     Vector2 direction = Vector2(1.0f, 0.0f);
+    bool is_active = false;
+
+    // 拖尾位置记录（视觉层）
+    std::vector<Vector2> trail_positions;
 
 protected:
     static void _bind_methods();
@@ -26,10 +41,17 @@ public:
     // 重置球到屏幕中央，以随机角度发射
     void reset();
 
+    // 活跃状态控制
+    void set_active(bool p_active);
+    bool get_active() const;
+
     // 属性 getter/setter
     void set_speed(float p_speed);
     float get_speed() const;
 
+    void set_initial_speed(float p_speed);
+    float get_initial_speed() const;
+
     // 信号: scored(int which) — 0=左边得分, 1=右边得分
 };
 
diff --git a/src/pingpong_game.cpp b/src/pingpong_game.cpp
index 9316ec2..ad98209 100644
--- a/src/pingpong_game.cpp
+++ b/src/pingpong_game.cpp
@@ -4,10 +4,21 @@
 #include <godot_cpp/core/class_db.hpp>
 #include <godot_cpp/variant/utility_functions.hpp>
 #include <godot_cpp/classes/engine.hpp>
+#include <godot_cpp/classes/input_event_key.hpp>
+#include <godot_cpp/classes/input.hpp>
 #include <godot_cpp/classes/scene_tree.hpp>
+#include <godot_cpp/classes/viewport.hpp>
 
 using namespace godot;
 
+// ═══════════════════════════════════════════════════════
+// 视觉颜色常量 — 以后替换素材时删除本段
+// ═══════════════════════════════════════════════════════
+static const Color FIELD_BG_COLOR = Color(0.06f, 0.10f, 0.18f);
+static const Color FIELD_BORDER_COLOR = Color(1.0f, 1.0f, 1.0f, 0.25f);
+static const Color FIELD_CENTER_LINE_COLOR = Color(1.0f, 1.0f, 1.0f, 0.12f);
+static const Color FIELD_CIRCLE_COLOR = Color(1.0f, 1.0f, 1.0f, 0.06f);
+
 void PingPongGame::_bind_methods() {
     // 属性
     ClassDB::bind_method(D_METHOD("get_left_score"), &PingPongGame::get_left_score);
@@ -24,6 +35,7 @@ void PingPongGame::_bind_methods() {
 
     // 方法
     ClassDB::bind_method(D_METHOD("reset_game"), &PingPongGame::reset_game);
+    ClassDB::bind_method(D_METHOD("start_countdown"), &PingPongGame::start_countdown);
     ClassDB::bind_method(D_METHOD("_on_ball_scored", "which"), &PingPongGame::_on_ball_scored);
 
     // 信号
@@ -34,41 +46,162 @@ PingPongGame::PingPongGame() {
     left_score = 0;
     right_score = 0;
     max_score = 5;
+    state = WAITING;
+    state_timer = 0.0f;
+    countdown_number = COUNTDOWN_START;
 }
 
 PingPongGame::~PingPongGame() {
 }
 
 void PingPongGame::_ready() {
-    // 查找比分 Label
+    // 查找子节点
     left_score_label = Object::cast_to<Label>(get_node_or_null("UI/LeftScore"));
     right_score_label = Object::cast_to<Label>(get_node_or_null("UI/RightScore"));
+    message_label = Object::cast_to<Label>(get_node_or_null("UI/Message"));
+    ball = Object::cast_to<PingPongBall>(get_node_or_null("Ball"));
 
     // 连接球的得分信号
-    PingPongBall *ball = Object::cast_to<PingPongBall>(get_node_or_null("Ball"));
     if (ball) {
         ball->connect("scored", Callable(this, "_on_ball_scored"));
     }
 
     update_score_display();
+    show_message("按空格键开始");
+}
+
+void PingPongGame::_process(double delta) {
+    queue_redraw();
+
+    switch (state) {
+    case WAITING:
+        // 等待用户按空格（在 _input 中处理）
+        break;
+
+    case COUNTDOWN: {
+        state_timer -= (float)delta;
+        if (state_timer <= 0.0f) {
+            countdown_number--;
+            if (countdown_number > 0) {
+                show_message(String::num_int64(countdown_number));
+                state_timer = COUNTDOWN_INTERVAL;
+            } else if (countdown_number == 0) {
+                show_message("GO!");
+                state_timer = COUNTDOWN_INTERVAL * 0.5f;
+            } else {
+                // 倒计时结束，开始游戏
+                show_message("");
+                set_state(PLAYING);
+                if (ball) {
+                    ball->set_active(true);
+                    ball->reset();
+                }
+            }
+        }
+        break;
+    }
+
+    case PLAYING:
+        // 正常游戏进行中，球和球拍自行运作
+        break;
+
+    case SCORED: {
+        state_timer -= (float)delta;
+        if (state_timer <= 0.0f) {
+            show_message("");
+            set_state(PLAYING);
+            if (ball) {
+                ball->set_active(true);
+                ball->reset();
+            }
+        }
+        break;
+    }
+
+    case GAME_OVER:
+        // 等待用户按空格重置
+        break;
+    }
+}
+
+void PingPongGame::_input(const Ref<InputEvent> &event) {
+    // 只有空格键按下事件
+    const InputEventKey *key_event = Object::cast_to<InputEventKey>(event.ptr());
+    if (!key_event || !key_event->is_pressed()) {
+        return;
+    }
+    if (key_event->get_keycode() != KEY_SPACE) {
+        return;
+    }
+
+    if (state == WAITING) {
+        start_countdown();
+    } else if (state == GAME_OVER) {
+        reset_game();
+        start_countdown();
+    }
+}
+
+// ═══════════════════════════════════════════════════════
+// 视觉层 — 场地绘制（几何体占位）
+// 替换方法：删除本方法 → 用 TileMap 或 Sprite2D 铺背景
+// ═══════════════════════════════════════════════════════
+void PingPongGame::_draw() {
+    Viewport *viewport = get_viewport();
+    if (!viewport) return;
+
+    Vector2 size = viewport->get_visible_rect().size;
+    float w = size.x;
+    float h = size.y;
+    float cx = w / 2.0f;
+    float cy = h / 2.0f;
+
+    // ── 场地背景 ──
+    draw_rect(Rect2(Vector2(0, 0), size), FIELD_BG_COLOR);
+
+    // ── 场地边界线 ──
+    float l = FIELD_INSET;
+    float r = w - FIELD_INSET;
+    float t = FIELD_INSET;
+    float b = h - FIELD_INSET;
+    draw_line(Vector2(l, t), Vector2(r, t), FIELD_BORDER_COLOR, 2.0f);
+    draw_line(Vector2(l, b), Vector2(r, b), FIELD_BORDER_COLOR, 2.0f);
+
+    // ── 虚线中线 ──
+    float dash_total = CENTER_LINE_DASH + CENTER_LINE_GAP;
+    for (float y = t; y < b; y += dash_total) {
+        float dash_end = MIN(y + CENTER_LINE_DASH, b);
+        draw_line(Vector2(cx, y), Vector2(cx, dash_end), FIELD_CENTER_LINE_COLOR, 1.5f);
+    }
+
+    // ── 中央发球圈 ──
+    draw_arc(Vector2(cx, cy), 80.0f, 0.0f, Math_PI * 2.0f, 32, FIELD_CIRCLE_COLOR, 1.5f);
 }
 
 void PingPongGame::_on_ball_scored(int which) {
     if (which == 0) {
-        // 左边得分
         right_score++;
     } else {
-        // 右边得分
         left_score++;
     }
-
     update_score_display();
 
+    if (ball) {
+        ball->set_active(false);
+    }
+
     // 检查是否有人获胜
     if (left_score >= max_score) {
+        show_message("玩家获胜！\n按空格键重新开始");
+        set_state(GAME_OVER);
         emit_signal("game_over", 0);
     } else if (right_score >= max_score) {
+        show_message("AI 获胜！\n按空格键重新开始");
+        set_state(GAME_OVER);
         emit_signal("game_over", 1);
+    } else {
+        show_message("得分！");
+        set_state(SCORED);
     }
 }
 
@@ -76,6 +209,33 @@ void PingPongGame::reset_game() {
     left_score = 0;
     right_score = 0;
     update_score_display();
+    if (ball) {
+        ball->set_active(false);
+        ball->reset();
+    }
+}
+
+void PingPongGame::start_countdown() {
+    countdown_number = COUNTDOWN_START;
+    state_timer = COUNTDOWN_INTERVAL;
+    set_state(COUNTDOWN);
+    show_message(String::num_int64(countdown_number));
+}
+
+void PingPongGame::set_state(GameState p_state) {
+    state = p_state;
+    state_timer = 0.0f;
+
+    if (p_state == SCORED) {
+        state_timer = SCORED_PAUSE;
+    }
+}
+
+void PingPongGame::show_message(const String &p_text) {
+    if (message_label) {
+        message_label->set_text(p_text);
+        message_label->set_visible(!p_text.is_empty());
+    }
 }
 
 void PingPongGame::update_score_display() {
diff --git a/src/pingpong_game.h b/src/pingpong_game.h
index 0e00b45..9c5c08d 100644
--- a/src/pingpong_game.h
+++ b/src/pingpong_game.h
@@ -3,9 +3,34 @@
 
 #include <godot_cpp/classes/node2d.hpp>
 #include <godot_cpp/classes/label.hpp>
+#include <godot_cpp/classes/input_event.hpp>
 
 namespace godot {
 
+class PingPongBall;
+
+// ═══════════════════════════════════════════════════════
+// 视觉常量 — 以后替换素材时删除本段
+// (颜色值定义在 pingpong_game.cpp 中)
+// ═══════════════════════════════════════════════════════
+static constexpr float FIELD_INSET = 15.0f;
+static constexpr float CENTER_LINE_DASH = 20.0f;
+static constexpr float CENTER_LINE_GAP = 12.0f;
+
+// 游戏状态
+enum GameState {
+    WAITING,
+    COUNTDOWN,
+    PLAYING,
+    SCORED,
+    GAME_OVER
+};
+
+// 倒计时参数
+static constexpr float COUNTDOWN_INTERVAL = 0.75f;
+static constexpr int COUNTDOWN_START = 3;
+static constexpr float SCORED_PAUSE = 1.2f;
+
 class PingPongGame : public Node2D {
     GDCLASS(PingPongGame, Node2D)
 
@@ -14,10 +39,20 @@ private:
     int right_score = 0;
     int max_score = 5;
 
+    // 状态机
+    GameState state = WAITING;
+    float state_timer = 0.0f;
+    int countdown_number = COUNTDOWN_START;
+
+    // 子节点引用
     Label *left_score_label = nullptr;
     Label *right_score_label = nullptr;
+    Label *message_label = nullptr;
+    PingPongBall *ball = nullptr;
 
     void update_score_display();
+    void set_state(GameState p_state);
+    void show_message(const String &p_text);
 
 protected:
     static void _bind_methods();
@@ -27,12 +62,16 @@ public:
     ~PingPongGame();
 
     void _ready() override;
+    void _process(double delta) override;
+    void _draw() override;
+    void _input(const Ref<InputEvent> &event) override;
 
     // 得分处理
     void _on_ball_scored(int which);
 
     // 重置整局游戏
     void reset_game();
+    void start_countdown();
 
     // 属性 getter/setter
     void set_left_score(int p_score);
diff --git a/src/pingpong_paddle.cpp b/src/pingpong_paddle.cpp
index f649f27..5ba72ce 100644
--- a/src/pingpong_paddle.cpp
+++ b/src/pingpong_paddle.cpp
@@ -1,6 +1,7 @@
 #include "pingpong_paddle.h"
 
 #include <godot_cpp/core/class_db.hpp>
+#include <godot_cpp/variant/utility_functions.hpp>
 #include <godot_cpp/classes/input.hpp>
 #include <godot_cpp/classes/engine.hpp>
 #include <godot_cpp/classes/node.hpp>
@@ -9,8 +10,13 @@
 
 using namespace godot;
 
+// ═══════════════════════════════════════════════════════
+// 视觉颜色常量 — 以后替换素材时删除本段
+// ═══════════════════════════════════════════════════════
+static const Color PADDLE_PLAYER_COLOR = Color(0.2f, 0.7f, 1.0f);
+static const Color PADDLE_AI_COLOR = Color(1.0f, 0.35f, 0.25f);
+
 void PingPongPaddle::_bind_methods() {
-    // 属性
     ClassDB::bind_method(D_METHOD("get_speed"), &PingPongPaddle::get_speed);
     ClassDB::bind_method(D_METHOD("set_speed", "value"), &PingPongPaddle::set_speed);
     ClassDB::add_property("PingPongPaddle", PropertyInfo(Variant::FLOAT, "speed"), "set_speed", "get_speed");
@@ -27,14 +33,33 @@ void PingPongPaddle::_bind_methods() {
 PingPongPaddle::PingPongPaddle() {
     speed = 350.0f;
     is_player = true;
+    ai_reaction_counter = 0.0f;
+    ai_target_y = 0.0f;
 }
 
 PingPongPaddle::~PingPongPaddle() {
 }
 
+// ═══════════════════════════════════════════════════════
+// 视觉层 — 圆角球拍（几何体占位）
+// 替换方法：删除本方法 → 添加 Sprite2D 子节点
+// ═══════════════════════════════════════════════════════
 void PingPongPaddle::_draw() {
-    // 画一个白色矩形表示球拍
-    draw_rect(Rect2(Vector2(-10.0f, -60.0f), Vector2(20.0f, 120.0f)), Color(1.0f, 1.0f, 1.0f));
+    Color color = is_player ? PADDLE_PLAYER_COLOR : PADDLE_AI_COLOR;
+    float hw = PADDLE_WIDTH / 2.0f;
+    float hh = PADDLE_HEIGHT / 2.0f;
+    float cr = PADDLE_CORNER_RADIUS;
+
+    // 主体矩形
+    draw_rect(Rect2(Vector2(-hw, -hh + cr), Vector2(PADDLE_WIDTH, PADDLE_HEIGHT - cr * 2.0f)), color);
+    // 上下两端矩形
+    draw_rect(Rect2(Vector2(-hw + cr, -hh), Vector2(PADDLE_WIDTH - cr * 2.0f, cr)), color);
+    draw_rect(Rect2(Vector2(-hw + cr, hh - cr), Vector2(PADDLE_WIDTH - cr * 2.0f, cr)), color);
+    // 四角圆形
+    draw_circle(Vector2(-hw + cr, -hh + cr), cr, color);
+    draw_circle(Vector2(hw - cr, -hh + cr), cr, color);
+    draw_circle(Vector2(-hw + cr, hh - cr), cr, color);
+    draw_circle(Vector2(hw - cr, hh - cr), cr, color);
 }
 
 void PingPongPaddle::_physics_process(double delta) {
@@ -42,7 +67,7 @@ void PingPongPaddle::_physics_process(double delta) {
     float move_amount = 0.0f;
 
     if (is_player) {
-        // 玩家控制：读取上下输入
+        // ── 玩家控制 ──
         Input *input = Input::get_singleton();
         if (input->is_action_pressed("ui_up")) {
             move_amount = -1.0f;
@@ -50,17 +75,29 @@ void PingPongPaddle::_physics_process(double delta) {
             move_amount = 1.0f;
         }
     } else {
-        // AI 控制：追踪球的位置
+        // ── AI 控制（有延迟和不精确性）──
         if (!ball_path.is_empty()) {
             Node *node = get_node_or_null(ball_path);
             if (node) {
                 Node2D *ball = Object::cast_to<Node2D>(node);
                 if (ball) {
                     float ball_y = ball->get_global_position().y;
+
+                    // 反应延迟计数器
+                    ai_reaction_counter -= (float)delta;
+                    if (ai_reaction_counter <= 0.0f) {
+                        // 更新目标位置（加入随机偏移）
+                        float noise = (UtilityFunctions::randf() - 0.5f) * 2.0f * AI_TRACKING_NOISE;
+                        ai_target_y = ball_y + noise;
+                        // 随机重置延迟
+                        ai_reaction_counter = AI_REACTION_DELAY_MIN +
+                            UtilityFunctions::randf() * (AI_REACTION_DELAY_MAX - AI_REACTION_DELAY_MIN);
+                    }
+
                     float paddle_y = get_global_position().y;
-                    if (ball_y < paddle_y - 20.0f) {
+                    if (ai_target_y < paddle_y - 15.0f) {
                         move_amount = -1.0f;
-                    } else if (ball_y > paddle_y + 20.0f) {
+                    } else if (ai_target_y > paddle_y + 15.0f) {
                         move_amount = 1.0f;
                     }
                 }
@@ -68,11 +105,12 @@ void PingPongPaddle::_physics_process(double delta) {
         }
     }
 
-    // 移动
-    Vector2 velocity = Vector2(0.0f, move_amount * speed * (float)delta);
+    // 移动（AI 速度略慢）
+    float effective_speed = is_player ? speed : speed * AI_SPEED_FACTOR;
+    Vector2 velocity = Vector2(0.0f, move_amount * effective_speed * (float)delta);
     move_and_collide(velocity);
 
-    // 限制移动范围（不超出屏幕）
+    // 限制移动范围
     Viewport *viewport = get_viewport();
     if (viewport) {
         Vector2 screen_size = viewport->get_visible_rect().size;
diff --git a/src/pingpong_paddle.h b/src/pingpong_paddle.h
index c8c64ef..81b9739 100644
--- a/src/pingpong_paddle.h
+++ b/src/pingpong_paddle.h
@@ -5,6 +5,20 @@
 
 namespace godot {
 
+// ═══════════════════════════════════════════════════════
+// 视觉常量 — 以后替换为 Sprite2D 时删除本段
+// (颜色值定义在 pingpong_paddle.cpp 中)
+// ═══════════════════════════════════════════════════════
+static constexpr float PADDLE_WIDTH = 18.0f;
+static constexpr float PADDLE_HEIGHT = 100.0f;
+static constexpr float PADDLE_CORNER_RADIUS = 6.0f;
+
+// AI 参数
+static constexpr float AI_SPEED_FACTOR = 0.85f;
+static constexpr float AI_REACTION_DELAY_MIN = 3.0f;
+static constexpr float AI_REACTION_DELAY_MAX = 10.0f;
+static constexpr float AI_TRACKING_NOISE = 30.0f;
+
 class PingPongPaddle : public CharacterBody2D {
     GDCLASS(PingPongPaddle, CharacterBody2D)
 
@@ -12,7 +26,11 @@ private:
     float speed = 350.0f;
     bool is_player = true;
     NodePath ball_path;
-    float half_height = 60.0f;  // 球拍半高，用于限制移动范围
+    float half_height = PADDLE_HEIGHT / 2.0f + 10.0f;
+
+    // AI 内部状态
+    float ai_reaction_counter = 0.0f;
+    float ai_target_y = 0.0f;
 
 protected:
     static void _bind_methods();
diff --git a/test.tmp b/test.tmp
new file mode 100644
index 0000000..587be6b
--- /dev/null
+++ b/test.tmp
@@ -0,0 +1 @@
+x