headerbar entry,
headerbar spinbutton,
headerbar button,
headerbar separator {
  margin-top: 0px;
  margin-bottom: 0px;
  min-height: 10px;
}

headerbar {
  min-height: 16px;
  padding-left: 2px;
  padding-right: 2px;
  margin: 0px;
  padding: 0px;
}