chromium/chrome/browser/resources/chromeos/supervision/supervised_user_offline.html

<style>
  #offline-screen {
    box-sizing: border-box;
    display: flex;
    flex-direction: column;
    height: 100%;
    justify-content: flex-start;
    padding: 26px 24px 20px;
  }

  .google-logo {
    width: 100px;
  }

  .offline-text {
    align-items: center;
    color: var(--cros-color-secondary);
    display: flex;
    font-size: 14px;
    margin-top: 26px;
  }

  .offline-title {
    font-family: var(--cros-font-family-google-sans);
    font-size: 24px;
    font-weight: 500;
    margin-top: 32px;
  }
</style>

<div id="offline-screen">
  <img class="google-logo" src="chrome://theme/IDR_LOGO_GOOGLE_COLOR_90"
    alt="Google">
  </img>
  <div class="offline-title">$i18n{supervisedUserOfflineTitle}</div>
  <div class="offline-text">$i18n{supervisedUserOfflineDescription}</div>
</div>