body {
    background-color: #f8f9fa;
    font-family: "Inter", "Segoe UI", sans-serif;
  }
  header {
    background: linear-gradient(135deg, #007bff, #0056b3);
    color: #fff;
    text-align: center;
    padding: 3.5rem 1rem 2rem;
    box-shadow: 0 3px 10px rgba(0,0,0,.15);
    position: relative;
  }
  header h1 {
    font-weight: 700;
    font-size: 2.7rem;
    letter-spacing: -0.5px;
  }
  header h1 .qr-box {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: #fff;
    color: #007bff;
    padding: 0.15em 0.25em 0.25em 0.15em;
    border-radius: 0.3rem;
    line-height: 1;
    margin-right: 0.15em;
  }
  header p {
    opacity: 0.95;
    margin-top: 0.5rem;
    font-size: 1.1rem;
  }
  .lang-switch {
    position: absolute;
    top: 1rem;
    right: 1rem;
  }
  .lang-switch button {
    background: rgba(255,255,255,0.2);
    color: #fff;
    border: none;
    margin-left: 0.25rem;
    padding: 0.3rem 0.7rem;
    border-radius: 0.3rem;
    cursor: pointer;
    transition: 0.2s;
  }
  .lang-switch button:hover, .lang-switch button.active {
    background: #fff;
    color: #007bff;
  }
  .card {
    border: none;
    border-radius: 1rem;
  }
  .btn-primary {
    background: #007bff;
    border: none;
    transition: all 0.2s ease-in-out;
  }
  .btn-primary:hover {
    background: #0056b3;
    transform: translateY(-2px);
  }
  #result {
    text-align: center;
    margin-top: 2rem;
    display: none;
  }
  #result img {
    max-width: 100%;
    height: auto;
    box-shadow: 0 2px 6px rgba(0,0,0,0.1);
    border-radius: .5rem;
  }
  footer {
    text-align: center;
    padding: 2rem 0;
    color: #6c757d;
    font-size: 0.9rem;
    border-top: 1px solid #dee2e6;
  }