body {
       font-family: system-ui, -apple-system, sans-serif;
       background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
       margin: 0;
       padding: 20px;
       min-height: 100vh;
   }

   .container {
       max-width: 800px;
       margin: 0 auto;
       background: white;
       padding: 30px;
       border-radius: 12px;
       box-shadow: 0 20px 60px rgba(0,0,0,0.3);
   }

   h1 {
       color: #667eea;
       margin: 0 0 10px 0;
   }

   button {
       background: #667eea;
       color: white;
       border: none;
       padding: 12px 24px;
       border-radius: 6px;
       font-size: 16px;
       cursor: pointer;
       margin-top: 20px;
   }

   button:hover {
       background: #5568d3;
   }

   #matrix-display {
       background: #000;
       padding: 20px;
       border-radius: 8px;
       margin: 20px 0;
       min-height: 200px;
       display: none;
   }

   #matrix-display.active {
       display: block;
   }