bootstrap table-bordered remove horizontal line

I would like to remove the bootstrap table-bordered horizontal line and keep the vertical line.

I have tried many solutions and done many of the research but I still cannot find the solution.

<div class="container">
    <div class="row">
        <div class="col-md-12">
            <table class="table table-bordered">
                <thead>
                    <tr>
                        <th>First Name</th>
                        <th>Last Name</th>
                    </tr>
                </thead>
                <tbody>
                    <tr>
                        <td>Otto</td>
                        <td>@mdo</td>
                    </tr>
                    <tr>
                        <td>Otto</td>
                        <td>@TwBootstrap</td>
                    </tr>
                    <tr>
                        <td>Thornton</td>
                        <td>@fat</td>
                    </tr>
                </tbody>
            </table>
        </div>
    </div>
</div>