Tables in html behaves differently than other elements on a page since the table, rows, th and td elements are displayed in a special way. The column width is automatically adjusted based on the content.

Here is a trick to set the column width using the colgroup element which affects both the th and td at once.

A table with 3 columns and 2 rows:

<table>
  <colgroup>
    <col class="col-select" />
    <col class="col-product" />
    <col class="col-country" />
  </colgroup>
  <thead>
    <tr>
      <th>Select</th>
      <th>Product</th>
      <th>Country</th>
    </tr>
  </thead>
  <tbody>
    <tr>
      <td><input type="checkbox">Select</td>
      <td>Product 1</td>
      <td>Sweden</td>
    </tr>
    <tr>
      <td><input type="checkbox">Select</td>
      <td>Product 2</td>
      <td>Norway</td>
    </tr>
  </tbody>
</table>

We have 3 columns: Select, Product and Country
To set the widths we use css classes col-select and so on.

.col-select { 
  width: 1%; 
} 
.col-product { 
  width: 75%; 
} 
.col-country {
  width: 24%; 
}

Here we set the select to be as “narrow” as possible (1%). And the others to relative % numbers.
To further “force” the widths we should allow long words to be wrapped, e.g add the following css class for the columns you wish this behavior for:

.text-break {
  overflow-wrap: break-word;
}

Usage:

<colgroup> 
  <col class="col-select" /> 
  <col class="col-product text-break" /> 
  <col class="col-country text-break" /> 
</colgroup>