[Shamun]

{if $bestsellers}
  {capture name=bestsellers}
    {if $cat eq '8'}
        <ul class="bestsellers-products-item-m">
    {elseif $cat eq '10'}
        <ul class="bestsellers-products-item-f">
    {else}
        <ul class="bestsellers-products-item">
    {/if}
      {foreach from=$bestsellers item=bestseller}
        <li>

try that.