loop.php

<div class="articles">
   <?php if (have_posts()): while (have_posts()) : the_post(); ?>
        <!-- article -->
        <article id="post-<?php the_ID(); ?>" <?php post_class(); ?>>

            <!-- post title -->
            <h2>
                <a href="<?php the_permalink(); ?>" title="<?php the_title(); ?>"><?php the_title(); ?></a>
            </h2>
            <!-- /post title -->
            <!-- post thumbnail -->
            <?php if ( has_post_thumbnail()) : // Check if thumbnail exists ?>
                <a href="<?php the_permalink(); ?>" title="<?php the_title(); ?>">
                   <amp-img class="home-image" src="<?php $thumb = wp_get_attachment_image_src( get_post_thumbnail_id($post->ID), 'large' ); echo $thumb['0'];?>" height="11.1" width="16" layout="responsive"></amp-img>
                </a>
            <?php endif; ?>
            <!-- /post thumbnail -->

        </article>
        <!-- /article -->

<?php endwhile; ?>

<?php else: ?>

	<!-- article -->
	<article>
		<h2><?php _e( 'Sorry, nothing to display.', 'ultraPhoto' ); ?></h2>
	</article>
	<!-- /article -->

<?php endif; ?>
</div>