#navbar .navbar-nav .nav-link {
  display: flex;
  flex-direction: column;
  align-items: center;
}

#navbar .navbar-nav .nav-link i {
  margin-bottom: 2px;
}

#navbar .navbar-nav .nav-link span {
  display: inline-block;
  width: 3em;            /* 控制一行能放两个汉字 */
  white-space: normal;
  word-break: break-all;
  text-align: center;
  line-height: 1.2;
  font-size: 0.9rem;
}