<div class="uk-section uk-section-default uk-flex uk-flex-middle" uk-height-viewport>
    <div class="uk-width-1-1">
        <div class="uk-container uk-container-small">

            <div class="uk-child-width-1-2@s" uk-grid>
                <div>

                    <h2 class="uk-h5 uk-heading-divider">Horizontal</h2>

                    <ul class="uk-thumbnav">
                        <li class="uk-active"><a href="#"><canvas width="100" height="70" class="test-img"></canvas></a></li>
                        <li><a href="#"><canvas width="100" height="70" class="test-img"></canvas></a></li>
                        <li><a href="#"><canvas width="100" height="70" class="test-img"></canvas></a></li>
                    </ul>

                </div>
                <div>

                    <h2 class="uk-h5 uk-heading-divider">Vertical</h2>

                    <ul class="uk-thumbnav uk-thumbnav-vertical">
                        <li class="uk-active"><a href="#"><canvas width="100" height="70" class="test-img"></canvas></a></li>
                        <li><a href="#"><canvas width="100" height="70" class="test-img"></canvas></a></li>
                        <li><a href="#"><canvas width="100" height="70" class="test-img"></canvas></a></li>
                    </ul>

                </div>
            </div>

        </div>
    </div>
</div>