body {
    background: linear-gradient(to right, #6dd5fa, #2980b9);
    height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
  }
  .card {
    width: 100%;
    max-width: 420px;
    border-radius: 1rem;
    box-shadow: 0 0 20px rgba(0,0,0,0.2);
  }