fix some minor issues

Author: wangyu-ustc

src/App.tsx

@@ -4,25 +4,18 @@ import { motion } from 'framer-motion';
 import { 
   Brain, 
   Database, 
-  Lock, 
-  Zap,
   Clock,
-  Settings,
   ArrowRight,
   Github,
-  Download,
   Code,
   Layers,
   Cpu,
   Shield,
   Terminal,
-  ChevronRight,
   Command
 } from 'lucide-react';
 import './App.css';
 import img0 from './assets/img0.png';
-import img1 from './assets/img1.png';
-import img3 from './assets/img3.png';
 
 function App() {
   const [isNavVisible, setIsNavVisible] = useState(true);