.site-header-inner{
  --header-icon-size: 18px;
}

.site-header-inner .mode-btn .nav-ph-ico,
.site-header-inner .header-utility-ico{
  width: var(--header-icon-size);
  height: var(--header-icon-size);
  min-width: var(--header-icon-size);
  min-height: var(--header-icon-size);
  font-size: var(--header-icon-size);
  line-height: 1;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  vertical-align: middle;
}

.site-header-inner #darkBtn .dark-btn-ico{
  width: var(--header-icon-size);
  height: var(--header-icon-size);
}