Reports

You have an extra <div class="container-fluid"> that is interfering with the row. If you just remove it everything will fall into place. You will also need to remove the order-x classes.

<body>
  <div class="row">

    <div class="col-16 bg-dark">
      <div class="d-flex justify-content-center">
        <h1 class="text-white">Welcome to the Website</h1>
      </div>
    </div>
    <div class="col-md-6 bg-dark">
      <div class="justify-content-center">
        <h1 class="text-white">Rate our website</h1>
      </div>
      <div class="justify-content-between">
        <button onclick="increasenumber()" id="coolbutton" type="button" class="btn btn-success">Upvote</button>
        <button onclick="decreasenumber()" id="coolbutton1" type="button" class="btn btn-danger">Downvote</button>
        <button onclick="resetcount()" id="coolbutton2" type="button" class="btn btn-info">Reset</button>
      </div>
      <div class="justify-content-center">
        <h1 class="text-white" id="counter">0</h1>
      </div>

    </div>
    <div class="col-md-4 bg-dark">

    </div>
  </div>

</body>

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