Product.tpl with variants, REFRESH problem

[giulym]

Hello,
I have a problem with product.tpl and product-variants.tpl when a product has combinations. I select a color and the page refreshes automatically to show the product variation, but input isn't checked anymore. This happens with all the variants (color, radio...). If I choose between 2 attributes in a dropdown input, page refreshes and the update doesn't stay checked. 
Do you know why this happens? 

product.tpl
 

              {block name='product_buy'}
                <form action="{$urls.pages.cart}" method="post" id="add-to-cart-or-refresh">
                  <input type="hidden" name="token" value="{$static_token}">
                  <input type="hidden" name="id_product" value="{$product.id}" id="product_page_product_id">
                  <input type="hidden" name="id_customization" value="{$product.id_customization}" id="product_customization_id">

                  {block name='product_variants'}
                    {include file='catalog/_partials/product-variants.tpl'}
                  {/block}

                                        {if $product.is_customizable && count($product.customizations.fields)}
                        {block name='product_customization'}
                            {include file="catalog/_partials/product-customization.tpl" customizations=$product.customizations}
                        {/block}
                    {/if}
                    
                    
                  {block name='product_add_to_cart'}
                    {include file='catalog/_partials/product-add-to-cart.tpl'}
                  {/block}

              

                  {* Input to refresh product HTML removed, block kept for compatibility with themes *}
                  {block name='product_refresh'}{/block}
                </form>
              {/block}

 

.color, .custom-checkbox input[type="checkbox"] + span.color {
    width: 10px;
    height: 10px;
    border: 5px solid red;
    display: inline-block;
    cursor: pointer;
    text-align: center;
    background-size: contain;
    border-radius: 50%;
}

product.tpl (miniatures)

<div class="product-variants">
  {foreach from=$groups key=id_attribute_group item=group}
    {if !empty($group.attributes)}
    <div class="clearfix product-variants-item">
      <span class="control-label">{$group.name}</span>
      {if $group.group_type == 'select'}
        <select
          class="form-control form-control-select"
          id="group_{$id_attribute_group}"
          data-product-attribute="{$id_attribute_group}"
          name="group[{$id_attribute_group}]">
          {foreach from=$group.attributes key=id_attribute item=group_attribute}
            <option value="{$id_attribute}" title="{$group_attribute.name}"{if $group_attribute.selected} selected="selected"{/if}>{$group_attribute.name}</option>
          {/foreach}
        </select>
      {elseif $group.group_type == 'color'}
        <ul id="group_{$id_attribute_group}">
          {foreach from=$group.attributes key=id_attribute item=group_attribute}
            <li class="float-xs-left input-container">
              <label>
                <input class="input-color" type="radio" data-product-attribute="{$id_attribute_group}" name="group[{$id_attribute_group}]" value="{$id_attribute}"{if $group_attribute.selected} checked="checked"{/if}>
                <span
                  {if $group_attribute.html_color_code}class="color" style="background-color: {$group_attribute.html_color_code}" {/if}
                  {if $group_attribute.texture}class="color texture" style="background-image: url({$group_attribute.texture})" {/if}
                ><span class="sr-only">{$group_attribute.name}</span></span>
              </label>
            </li>
          {/foreach}
        </ul>
        
      {elseif $group.group_type == 'radio'}
        <ul id="group_{$id_attribute_group}">
            
          {foreach from=$group.attributes key=id_attribute item=group_attribute}
            <li class="input-container float-xs-left">
              <label>
                <input class="input-radio" type="radio" data-product-attribute="{$id_attribute_group}" name="group[{$id_attribute_group}]" value="{$id_attribute}"{if $group_attribute.selected} checked="checked"{/if} required>
                <span class="radio-label">{$group_attribute.name}</span>
              </label>
            </li>
          {/foreach}
        </ul>
      {/if}
    </div>
    {/if}
  {/foreach}
</div>