JSFiddle - React, Tailwind, and code Playground

HTML

<div class="item-buttons">
  <div class="group-buttons">
    <button class="btn green minus">-</button>
    <input class="btn-input item-count" type="text" value="1">
    <button class="btn green plus">+</button>
  </div>
  <div>
    <input class="btn green add-to-cart" type="button" data-id="1" data-action= "addToBasket" value="В корзину" >
  </div>
 
 
   <div class="group-buttons">
    <button class="btn green minus">-</button>
    <input class="btn-input item-count" type="text" value="1">
    <button class="btn green plus">+</button>
  </div>
  <div>
    <input class="btn green add-to-cart" type="button" data-id="2" data-action= "addToBasket" value="В корзину" >
  </div>
</div>

CSS

body {
  width: 20%;
}
.item-buttons {
    display: flex;
    justify-content: space-between;
    flex-direction: column;

}

.item-buttons .btn-input {
    width: 30px;
    text-align: center;
    font-size: 15px;
    background: #f8f8f8;
    border: 1px solid #bfbbbb;

}
.group-buttons {
    display: flex;
    margin: 20px 0;
}
.btn {
  padding: 7px 12px;
  color: white;
  border: 0;
  cursor: pointer;
  text-shadow: none;
  transition: all .3s;
  background: #000;

}

JavaScript

$('.minus').on('click', function() {
      $input = $(this).parent().find('input');
      $count = parseInt($input.val()) - 1;
      $count = $count < 1 ? 1 : $count;
      $input.val($count);
      $input.change();
      return false;
    });

    $('.plus').on('click',function() {
        var $input = $(this).parent().find('input');
        $input.val(parseInt($input.val()) + 1);
        $input.change();
        return false;
    });
    


		/*добавляю товар в корзину*/

  $('.add-to-cart').on('click',function() {
    
    id = $(this).attr('data-id');
    addToBasket = $(this).attr('data-action');
		
    $.ajax({
      type: 'POST',
      url: 'cart.php',
      data: { id : id, action: addToBasket},
      success:function (data) { 
        $('.cart-content').html(data);
      },    
    });
    

    return false;

  });