[Dilettante_Pro]

<div class="col-lg-4 col-md-4 col-sm-5 hidden-xs text-center cart-color-1">
	<span id="head-cart">К оплате: </span>
        <h2 class="summa_result"></h2> 
        <span> грн</span>
</div>
<div class="col-lg-2 col-md-2 col-sm-2">
	<h2 class="clac_summa">32997</h2>
        <span>грн</span>
</div>
<div class="col-lg-2 col-md-2 col-sm-2">
	<h2 class="clac_summa">29997</h2>
        <span>грн</span>
</div>
<script>
 var items = document.querySelectorAll('.clac_summa'),
      summa = 0;
  [].forEach.call( items, function(el) {
       summa += +el.innerText;
});
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</script>