:root {
        --main: #2379cc;
        --main-dark: #1c477a;
        --bg: #f6faff;
      }
      body {
        background: var(--bg);
        margin: 0;
        font-family: "Segoe UI", Arial, sans-serif;
        color: #234;
      }
      .container {
        max-width: 430px;
        margin: 38px auto 0 auto;
        background: #fff;
        border-radius: 18px;
        box-shadow: 0 4px 22px #2379cc33;
        padding: 28px 18px 22px 18px;
      }
      .logo {
        font-size: 1.13em;
        font-weight: bold;
        text-align: center;
        color: var(--main-dark);
        margin-bottom: 9px;
      }
      .desc {
        text-align: center;
        color: #2879b8;
        margin-bottom: 18px;
        font-size: 0.79em;
      }
      .input-row {
        display: flex;
        align-items: center;
        gap: 7px;
        margin-bottom: 11px;
      }
      .input-row label {
        min-width: 98px;
        color: #286473;
        font-size: 0.99em;
      }
      .input-row select,
      .input-row input[type="text"] {
        flex: 1;
        padding: 8px 8px;
        font-size: 1.04em;
        border: 1px solid #afd4f6;
        border-radius: 7px;
        background: #fafdff;
        color: #234;
      }
      .input-row input[type="text"] {
        width: 100%;
      }
      .barcode-options {
        text-align: right;
        font-size: 0.75em;
        color: #2277b9;
      }
      .action-btn {
        background: var(--main);
        color: #fff;
        border: none;
        border-radius: 8px;
        padding: 12px 0;
        width: 100%;
        font-size: 1.13em;
        font-weight: bold;
        cursor: pointer;
        margin-top: 10px;
        margin-bottom: 14px;
        box-shadow: 0 2px 12px #2379cc28;
        transition: background 0.15s;
      }
      .action-btn:active {
        background: var(--main-dark);
      }
      .info-msg {
        color: #e44;
        text-align: center;
        font-size: 1.03em;
        margin: 4px 0 8px 0;
      }
      .barcode-area {
        text-align: center;
        margin: 20px 0 7px 0;
        min-height: 120px;
      }
      .footer {
        color: #789;
        text-align: center;
        font-size: 0.93em;
        margin-top: 16px;
      }
      #backBtn {
        position: fixed;
        left: 50%;
        bottom: 32px;
        transform: translateX(-50%);
        background: #2379cc;
        color: #fff;
        font-weight: 700;
        border: none;
        border-radius: 2rem;
        padding: 0.58em 1.5em;
        box-shadow: 0 4px 16px #13d2b066;
        font-size: 1.09em;
        text-decoration: none;
        cursor: pointer;
        letter-spacing: 0.01em;
        transition:
          background 0.15s,
          transform 0.12s;
        z-index: 2000;
      }
      #backBtn:hover {
        background: #1c477a;
        transform: translateX(-50%) scale(1.04);
      }
      @media (max-width: 600px) {
        .container {
          max-width: 99vw;
          padding: 12px 2vw 12px 2vw;
        }
        #backBtn { bottom: 18px; font-size: 0.98em; padding: 0.48em 1em; }
      }
      .faq-block {
        margin: 25px 0 12px 0;
        border-top: 1.5px dashed #b7d3e9;
        padding-top: 13px;
        font-size: 1.04em;
      }
      .faq-block details { margin-bottom: 7px; }
      .faq-block summary {
        font-weight: 600;
        color: #187be6;
        cursor: pointer;
        font-size: 1.01em;
      }
      .faq-block p { margin: 4px 0 1px 0; }