div>
          <div class="pad__slot r2 c1">
            <button class="key" type="button">5</button>
          </div>
          <div class="pad__slot r2 c2">
            <button class="key" type="button">6</button>
          </div>
          <div class="pad__slot r2 c3">
            <button class="key" type="button">+</button>
          </div>

          <div class="pad__slot r3 c0">
            <button class="key" type="button">1</button>
          </div>
          <div class="pad__slot r3 c1">
          