.container {
    width: 100%;
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
  }

  /* Header da ferramenta */
  .tool-header {
    text-align: center;
    padding: clamp(20px, 6vw, 40px) 0 clamp(16px, 4vw, 32px);
  }
  .tool-header h1 {
    font-size: clamp(28px, 6vw, 42px);
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--text-color);
    margin-bottom: 12px;
    line-height: 1.2;
  }
  .badge {
    background: linear-gradient(135deg, var(--primary-light), var(--primary));
    font-size: 0.6em;
    padding: 4px 10px;
    border-radius: 40px;
    color: white;
    vertical-align: middle;
    margin-left: 8px;
    display: inline-block;
    white-space: nowrap;
  }
  .tool-header p {
    font-size: clamp(0.9rem, 4vw, 1.125rem);
    color: var(--gray);
    max-width: 700px;
    margin: 0 auto;
    padding: 0 16px;
  }

  /* Grid principal: duas colunas (configuração + prévia) */
  .qr-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 28px;
    margin: 32px 0 48px;
  }

  /* Cards das colunas */
  .qr-config, .qr-preview {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    box-shadow: var(--card-shadow);
    border: 1px solid var(--border-color);
    overflow: hidden;
    transition: var(--transition);
    display: flex;
    flex-direction: column;
  }

  /* Cabeçalho dos cards */
  .panel-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 20px;
    background: var(--bg-light);
    border-bottom: 1px solid var(--border-color);
    font-weight: 600;
    font-size: 1rem;
    color: var(--text-color);
  }
  .btn-icon {
    background: transparent;
    border: none;
    font-size: 1.2rem;
    cursor: pointer;
    padding: 6px 10px;
    border-radius: 30px;
    transition: var(--transition);
    color: var(--gray);
  }
  .btn-icon:hover {
    background: var(--border-color);
    color: var(--danger);
  }

  /* Corpo dos cards */
  .panel-body {
    padding: clamp(16px, 5vw, 24px);
    flex: 1;
  }

  /* Labels */
  label {
    display: block;
    font-size: 0.9rem;
    font-weight: 500;
    margin-bottom: 8px;
    color: var(--text-color);
  }

  /* Textarea e selects */
  textarea {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid var(--input-border, var(--border-color));
    border-radius: 12px;
    background: var(--input-bg, var(--bg-light));
    color: var(--text-color);
    font-family: inherit;
    font-size: 0.95rem;
    resize: vertical;
    transition: var(--transition);
  }
  textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(67, 97, 238, 0.1);
  }

  .select-modern {
    width: 100%;
    padding: 12px 14px;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    background: var(--input-bg, var(--bg-light));
    font-size: 0.95rem;
    color: var(--text-color);
    cursor: pointer;
    margin-top: 4px;
  }

  /* Botões de ação */
  .action-bar {
    display: flex;
    gap: 16px;
    justify-content: flex-start;
    flex-wrap: wrap;
    margin-top: 24px;
  }
  .btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 24px;
    border-radius: 40px;
    font-weight: 600;
    font-size: 0.9rem;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    background: var(--primary);
    color: white;
  }
  .btn-primary {
    background: var(--primary);
    box-shadow: 0 2px 6px rgba(67, 97, 238, 0.2);
  }
  .btn-primary:hover:not(:disabled) {
    background: var(--primary-dark);
    transform: translateY(-2px);
  }
  .btn-secondary {
    background: var(--gray-light);
    background-color: #64748b;
  }
  .btn-secondary:not(:disabled) {
    background: var(--secondary);
  }
  .btn-secondary:not(:disabled):hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
  }
  .btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
  }

  /* Área de prévia do QR Code */
  .qr-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 300px;
    padding: 24px;
    background: var(--bg-light);
    flex: 1;
  }
  .qr-placeholder {
    text-align: center;
    color: var(--gray);
    font-size: 1rem;
  }
  #qrCodeDisplay {
    display: flex;
    justify-content: center;
    align-items: center;
    width: 100%;
  }
  #qrCodeDisplay canvas {
    max-width: 100%;
    height: auto;
    border-radius: 16px;
    box-shadow: var(--card-shadow);
    background: white;
    padding: 8px;
  }

  /* Dica abaixo do QR */
  .hint {
    margin-top: 16px;
    text-align: center;
    font-size: 0.8rem;
    color: var(--gray);
    padding-bottom: 20px;
  }

  /* Card de informações (dicas) */
  .info-card {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    padding: clamp(18px, 4vw, 28px);
    box-shadow: var(--card-shadow);
    border: 1px solid var(--border-color);
    margin: 32px auto 48px;
    max-width: 100%;
  }
  .info-card h3 {
    font-size: clamp(1.1rem, 4vw, 1.3rem);
    margin-bottom: 16px;
    font-weight: 600;
    color: var(--text-color);
  }
  .info-card ul {
    list-style: none;
    padding-left: 0;
  }
  .info-card li {
    padding-left: 24px;
    position: relative;
    margin-bottom: 12px;
    font-size: clamp(0.85rem, 3vw, 0.95rem);
    color: var(--gray);
    line-height: 1.4;
  }
  .info-card li::before {
    content: "✓";
    position: absolute;
    left: 0;
    color: var(--primary);
    font-weight: bold;
  }

  /* ===== RESPONSIVIDADE ===== */

  /* Telas médias (até 900px) – ajuste de padding */
  @media (max-width: 900px) {
    .container {
      padding: 0 20px;
    }
  }

  /* Tablets e mobile landscape (até 768px) – grid empilhado */
  @media (max-width: 768px) {
    .qr-grid {
      grid-template-columns: 1fr;
      gap: 24px;
      margin: 24px 0 32px;
    }
    .action-bar {
      flex-direction: column;
    }
    .btn {
      width: 100%;
      justify-content: center;
    }
    .panel-header {
      padding: 12px 16px;
    }
    .panel-body {
      padding: 18px;
    }
    .qr-container {
      min-height: 280px;
      padding: 16px;
    }
  }

  /* Celulares pequenos (até 480px) – compactação máxima */
  @media (max-width: 480px) {
    .container {
      padding: 0 16px;
    }
    .tool-header h1 {
      font-size: 1.8rem;
    }
    .badge {
      font-size: 0.55em;
      margin-left: 4px;
      padding: 3px 8px;
    }
    .tool-header p {
      font-size: 0.85rem;
    }
    textarea, .select-modern {
      font-size: 0.85rem;
      padding: 10px 12px;
    }
    .btn {
      padding: 10px 20px;
      font-size: 0.85rem;
    }
    .qr-container {
      min-height: 240px;
      padding: 12px;
    }
    .hint {
      font-size: 0.7rem;
    }
    .info-card li {
      font-size: 0.75rem;
    }
  }

  /* Orientação landscape em dispositivos móveis */
  @media (max-width: 800px) and (orientation: landscape) {
    .qr-grid {
      gap: 16px;
    }
    .qr-container {
      min-height: 220px;
    }
    .action-bar {
      flex-direction: row;
    }
    .btn {
      width: auto;
      flex: 1;
    }
  }

  /* Telas muito grandes (acima de 1600px) – centralização */
  @media (min-width: 1600px) {
    .container {
      max-width: 1400px;
    }
    .qr-config, .qr-preview {
      max-width: 700px;
      margin: 0 auto;
    }
    .qr-grid {
      justify-content: center;
    }
  }