#plc-app {
    max-width: 760px;
    margin: 2rem auto;
    background: #fff;
    border-radius: 12px;
    padding: 1.5rem;
    box-shadow: 0 6px 24px rgba(0,0,0,0.06);
    font-family: system-ui, Arial, sans-serif;
  }
  #plc-app h2 {
    margin-top: 0;
    text-align: center;
  }
  #plc-form .plc-grid {
    display: grid;
    gap: 12px;
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  @media (max-width: 640px) {
    #plc-form .plc-grid { grid-template-columns: 1fr; }
  }
  #plc-form label {
    display: grid;
    gap: 6px;
    font-size: 0.95rem;
  }
  #plc-form input[type="number"] {
    padding: 10px;
    border: 1px solid #d7d7d7;
    border-radius: 8px;
    font-size: 1rem;
    width: 100%;
  }
  #plc-btn {
    margin-top: 12px;
    width: 100%;
    padding: 12px 14px;
    border: 0;
    border-radius: 10px;
    background: #0a66ff;
    color: #fff;
    font-weight: 600;
    cursor: pointer;
  }
  #plc-btn:hover { background: #0447b5; }
  .plc-results { margin-top: 1rem; }
  .plc-results .plc-msg { margin: 0.4rem 0; font-weight: 600; }