JSFiddle - React, Tailwind, and code Playground

HTML

<input type="text" id="username" placeholder="username"/>
<button id="search-btn">
  Search
</button>
<hr>
<table id="results" width="100%">
  <thead>
    <th>
      Username
    </th>
      <th>
      Repositories
    </th>  
  </thead>
  <tbody>
    <tr>
      <td>
        User1<br/>
      </td>
      <td>
        repo1<br/>
        repo2<br/>
      </td>
    </tr>
    <tr>
      <td>
        User2<br/>
      </td>
      <td>
        repo1<br/>
        repo2<br/>
      </td>
    </tr>
  </tbody>
</table>

CSS

td {
  border-bottom: 1px solid black
}