<style>
  /* .nav-tabs 하위의 모든 a 태그에 폰트 크기를 small로 적용 */
  .nav-tabs a {
    font-size: 0.875em;
    /* Bootstrap .small 크기 */
  }
</style>
<ul class="nav nav-tabs">
  <li class="nav-item">
    <span class="nav-item navbar-brand" aria-current="page">
      <h4>&nbsp;&nbsp;<?= ICONS['DESKTOP'] ?> <?= $viewDatas['title'] ?? "" ?>&nbsp;&nbsp;</h4>
    </span>
  </li>
  <li class="nav-item">
    <span class="nav-link active" aria-current="page" style="cursor:pointer;"><a
        href="/admin/customer/client">고객정보</a></span>
  </li>
</ul>