body {
      font-family: "Inter", sans-serif;
      background: #f9fafb;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      height: 100vh;
      margin: 0;
    }
    .container {
      background: #fff;
      padding: 2rem;
      border-radius: 8px;
      box-shadow: 0 4px 6px rgba(0,0,0,0.1);
      text-align: center;
      max-width: 500px;
      width: 90%;
    }
    h1 {
      color: #4f46e5;
      margin-bottom: 1rem;
    }
    p {
      color: #374151;
      margin-bottom: 2rem;
    }
    button {
      padding: 0.75rem 1.5rem;
      font-size: 1.125rem;
      color: #fff;
      background: #4f46e5;
      border: none;
      border-radius: 4px;
      cursor: pointer;
      transition: background 0.3s;
    }
    button:hover {
      background: #4338ca;
    }
    #loading {
      display: none;
      margin-top: 1rem;
      color: #374151;
      font-size: 1.125rem;
    }