-1
I don’t know what happens, but when I start the screen with the display block in the odd id, everything ok but when disabled, and enabled again, the column fields appear all in the first column
function Mudarestado(el) {
  var display = document.getElementById(el).style.display;
  if (display == "none") {
    document.getElementById(el).style.display = 'block';
  } else {
    document.getElementById(el).style.display = 'none';
  }
}
table {
  width: 100%;
  height: 100%;
}
thead tr {
  background-color: ActiveCaption;
  color: CaptionText;
}
th,
td {
  vertical-align: top;
  font-family: "Tahoma";
  font-size: 10pt;
  text-align: left;
  cursor: pointer;
}
#impar {
  display: none;
}
<table>
  <thead>
    <tr>
      <th class="col0">COLUNA 1</th>
      <th class="col1">COLUNA 2</th>
      <th class="col2">COLUNA 3</th>
    </tr>
  </thead>
  <tbody>
    <tr id="par" onclick="Mudarestado('impar')">
      <td class="col0">CAMPO DA COLUNA 1</td>
      <td class="col1">CAMPO DA COLUNA 2</td>
      <td class="col2">CAMPO DA COLUNA 3</td>
    </tr>
    <tr id="impar">
      <td>CAMPO OBSERVACAO DA COLUNA 1</td>
      <td>CAMPO OBSERVACAO DA COLUNA 2</td>
      <td>CAMPO OBSERVACAO DA COLUNA 3</td>
    </tr>
  </tbody>
</table>
Thank you very much!!!
– Natan Braun