<ul class="accordion">
<li class="accordion-item is-active">
<h3 class="accordion-thumb">{{ product.metafields.my_fields.first_tab_title }}</h3>
<p class="accordion-panel">{{ product.metafields.my_fields.first_tab_description }}</p>
</li>
<li class="accordion-item">
<h3 class="accordion-thumb">{{ product.metafields.my_fields.second_tab_title }}</h3>
<p class="accordion-panel">{{ product.metafields.my_fields.second_tab_description }}</p>
</li>
<li class="accordion-item">
<h3 class="accordion-thumb">{{ product.metafields.my_fields.third_tab_title }}</h3>
<p class="accordion-panel">{{ product.metafields.my_fields.third_tab_description }}</p>
</li>
</ul>