diff --git a/components/top-navbar.tsx b/components/top-navbar.tsx
index 77f85150c..f51ab693f 100644
--- a/components/top-navbar.tsx
+++ b/components/top-navbar.tsx
@@ -6,6 +6,7 @@ import { Settings, ExternalLink, Briefcase, Images, Sparkles, Trophy, Building2,
 import { Button } from "@/components/ui/button";
 import { useTheme } from "next-themes";
 import { useState, useEffect, useRef } from "react";
+import { createPortal } from "react-dom";
 import {
   DropdownMenu,
   DropdownMenuContent,
@@ -152,7 +153,7 @@ export function TopNavbar({
     setEditorImageUrl("");
   };
 
-  return (
+  const navContent = (
     <nav className="fixed top-0 left-0 right-0 z-[100] flex h-12 items-center justify-between bg-black/90 backdrop-blur-sm px-4 text-white border-b border-white/10 shadow-sm">
       {/* 左侧：LOGO + 网站名称 */}
       <a 
@@ -446,89 +447,93 @@ export function TopNavbar({
           onCancel={handleImageEditorCancel}
         />
       )}
+    </nav>
+  );
 
-      {/* 功能教程弹窗 - 全屏居中 */}
-      {showTutorialModal && currentTutorialVideo && (
-        <div 
-          className="fixed inset-0 z-[99999] bg-black/95"
-          style={{ 
-            position: 'fixed',
-            top: 0,
-            left: 0,
-            right: 0,
-            bottom: 0,
-            display: 'flex',
-            alignItems: 'center',
-            justifyContent: 'center',
-            margin: 0,
-            padding: '20px',
-          }}
+  // 使用 Portal 将视频弹窗渲染到 body，确保它在最顶层且不受 nav 的限制
+  const videoModal = showTutorialModal && currentTutorialVideo && typeof document !== 'undefined' ? createPortal(
+    <div 
+      className="fixed inset-0 z-[99999] bg-black/95"
+      style={{ 
+        position: 'fixed',
+        top: 0,
+        left: 0,
+        right: 0,
+        bottom: 0,
+        display: 'flex',
+        alignItems: 'center',
+        justifyContent: 'center',
+        margin: 0,
+        padding: '20px',
+      }}
+      onClick={() => {
+        setShowTutorialModal(false);
+        setCurrentTutorialVideo(null);
+      }}
+    >
+      <div 
+        className="relative w-full max-w-[1200px]"
+        style={{ maxHeight: 'calc(100vh - 40px)' }}
+        onClick={(e) => e.stopPropagation()}
+      >
+        {/* 关闭按钮 */}
+        <button
           onClick={() => {
             setShowTutorialModal(false);
             setCurrentTutorialVideo(null);
           }}
+          className="absolute -top-10 right-0 text-white hover:text-red-400 transition-colors z-10"
+          title="关闭 (ESC)"
         >
-          <div 
-            className="relative w-full max-w-[1200px]"
-            style={{ maxHeight: 'calc(100vh - 40px)' }}
-            onClick={(e) => e.stopPropagation()}
-          >
-            {/* 关闭按钮 - 右上角固定 */}
-            <button
-              onClick={() => {
-                setShowTutorialModal(false);
-                setCurrentTutorialVideo(null);
-              }}
-              className="absolute -top-10 right-0 text-white hover:text-red-400 transition-colors z-10"
-              style={{ position: 'absolute', top: '-40px', right: '0' }}
-              title="关闭 (ESC)"
-            >
-              <X className="h-8 w-8" />
-            </button>
-            
-            {/* 标题 */}
-            <h3 className="text-white text-lg font-medium mb-3 text-center truncate px-4">{currentTutorialVideo.title}</h3>
-            
-            {/* 视频播放器 */}
-            {currentTutorialVideo.videoUrl.includes('youtube.com') || currentTutorialVideo.videoUrl.includes('youtu.be') ? (
-              // YouTube 嵌入 - 启用自动播放和性能优化
-              <div className="relative w-full aspect-video bg-black rounded-lg overflow-hidden shadow-2xl">
-                <iframe
-                  src={`${currentTutorialVideo.videoUrl.replace('watch?v=', 'embed/').replace('youtu.be/', 'youtube.com/embed/')}?autoplay=1&rel=0&modestbranding=1`}
-                  className="w-full h-full"
-                  allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share"
-                  allowFullScreen
-                  loading="eager"
-                />
-              </div>
-            ) : currentTutorialVideo.videoUrl.includes('bilibili.com') ? (
-              // Bilibili 嵌入
-              <div className="relative w-full aspect-video bg-black rounded-lg overflow-hidden shadow-2xl">
-                <iframe
-                  src={`${currentTutorialVideo.videoUrl.replace('www.bilibili.com/video/', 'player.bilibili.com/player.html?bvid=')}&autoplay=1&high_quality=1`}
-                  className="w-full h-full"
-                  allowFullScreen
-                  loading="eager"
-                />
-              </div>
-            ) : (
-              // 自定义高性能视频播放器 - 针对慢速网络优化
-              <VideoPlayer
-                src={currentTutorialVideo.videoUrl}
-                poster={currentTutorialVideo.coverUrl || undefined}
-                title={currentTutorialVideo.title}
-                autoPlay={true}
-                className="shadow-2xl"
-              />
-            )}
-
-            {/* 视频描述 */}
-            {currentTutorialVideo.description && (
-              <p className="text-gray-300 text-sm mt-3">{currentTutorialVideo.description}</p>
-            )}
+          <X className="h-8 w-8" />
+        </button>
+        
+        {/* 标题 */}
+        <h3 className="text-white text-lg font-medium mb-3 text-center truncate px-4">{currentTutorialVideo.title}</h3>
+        
+        {/* 视频播放器 */}
+        {currentTutorialVideo.videoUrl.includes('youtube.com') || currentTutorialVideo.videoUrl.includes('youtu.be') ? (
+          <div className="relative w-full aspect-video bg-black rounded-lg overflow-hidden shadow-2xl">
+            <iframe
+              src={`${currentTutorialVideo.videoUrl.replace('watch?v=', 'embed/').replace('youtu.be/', 'youtube.com/embed/')}?autoplay=1&rel=0&modestbranding=1`}
+              className="w-full h-full"
+              allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share"
+              allowFullScreen
+              loading="eager"
+            />
           </div>
-        </div>
-      )}
-    </nav>
+        ) : currentTutorialVideo.videoUrl.includes('bilibili.com') ? (
+          <div className="relative w-full aspect-video bg-black rounded-lg overflow-hidden shadow-2xl">
+            <iframe
+              src={`${currentTutorialVideo.videoUrl.replace('www.bilibili.com/video/', 'player.bilibili.com/player.html?bvid=')}&autoplay=1&high_quality=1`}
+              className="w-full h-full"
+              allowFullScreen
+              loading="eager"
+            />
+          </div>
+        ) : (
+          <VideoPlayer
+            src={currentTutorialVideo.videoUrl}
+            poster={currentTutorialVideo.coverUrl || undefined}
+            title={currentTutorialVideo.title}
+            autoPlay={true}
+            className="shadow-2xl"
+          />
+        )}
+
+        {/* 视频描述 */}
+        {currentTutorialVideo.description && (
+          <p className="text-gray-300 text-sm mt-3 text-center">{currentTutorialVideo.description}</p>
+        )}
+      </div>
+    </div>,
+    document.body
+  ) : null;
+
+  return (
+    <>
+      {navContent}
+      {videoModal}
+    </>
   );
 }