WebContainer Playground

📝 index.js

import express from 'express';

const app = express();
const port = 3000;

app.get('/', (req, res) => {
  res.send(`
    <html>
      <head>
        <style>
          body { 
            font-family: system-ui; 
            display: flex; 
            justify-content: center; 
            align-items: center; 
            min-height: 100vh; 
            margin: 0;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
            color: white;
          }
          .card {
            background: rgba(255,255,255,0.1);
            padding: 2rem 3rem;
            border-radius: 16px;
            text-align: center;
            backdrop-filter: blur(10px);
          }
          h1 { margin: 0 0 1rem 0; font-size: 2.5rem; }
          p { opacity: 0.9; }
        </style>
      </head>
      <body>
        <div class="card">
          <h1>Hello from WebContainer! 🎉</h1>
          <p>This Express server is running entirely in your browser.</p>
          <p>Server time: ${new Date().toLocaleTimeString()}</p>
        </div>
      </body>
    </html>
  `);
});

app.listen(port, () => {
  console.log(`Server running at http://localhost:${port}`);
});

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