JSFiddle - React, Tailwind, and code Playground

HTML

<table>
  <thead>
    <tr>
      <th>
          <div class="container">
        <span class="resize"> </span>
        <div class="label">
          Column 1
        </div>
          </div>
      </th>
      <th>
          <div class="container">
        <span class="resize"> </span>
        <div class="label">
          Column 2
        </div>
           </div>
      </th>
    </tr>
  </thead>
</table>

CSS

table thead th {
  position: relative;
}

.container {
position: relative;
text-align:right;
}

table thead th span.resize {
  width: 8px;
  background-color: gray;
  position: absolute;
  right: 50px;
  top: 0px;
  bottom: 0px;
  z-index: 1;
  cursor: col-resize;
}