.webform-options-display-buttons input:checked + label.webform-options-display-buttons-label {
  color: #fff;
  border-color: #000000;
  background-color: #000;
}
.webform-options-display-buttons label.webform-options-display-buttons-label {
  border-radius: 0px;
  border-color: #000;
  color: #000;
}