</div>
<div class="row">
  <button id="num-4">4</button>
  <button id="num-5">5</button>
  <button id="num-6">6</button>
  <button id="minus">-</button>
</div>
<div class="row">
  <button id="num-1">1</button>
  <button id="num-2">2</button>
  <button id="num-3">3</button>
  <button id="divide">/</button>
</div>
<div class="row">
  <button id="clear">C</button>
  <button id="num-0">0</button>
  <button id="calculate">=</button>
  <button id="multiply">x</button>
</div>
<script>
</script>
</body>