src/dctv/gui.css

ExceptionDisplayWidget {
  color: red;
}

.pivot_agg_button {
  padding: 0;
  margin: 0;
  min-height: 0;
}

.pivot_agg_button > label {
  margin: 0;
  padding: 0;
  margin-left: 0.5em;
}

FhView > FhViewHeader > button > button {
  border: 0;
}

FhView > FhViewHeader > button {
  border: 1px inset;
  border-right: 0;
  padding: 0;
  margin: 0;
  border-radius: 0;
  transition: none;
}

FhView > FhViewHeader > button:first-child {
  border-left: 0;
}

FhView > FhViewHeader > button.dnd {
  border-left: 1px inset;
  border-right: 1px inset;
  border-top: 5px solid red;
}

FhView > FhViewHeader > button.rownumber > button {
  padding-left: 1em;
  padding-right: 1em;
}