WordPress WordPress Theme Development Adding a Blog to a WordPress Theme Coding the Blog Homepage

div overflow

For some reason my excerp is overflowing from its div for the first post of the blog but the second post of the blog is fine. The same applies to my static pages. They aren't contained within their div. Can anybody help me with this?

This is the code for my blog post: <?php get_header(); ?>

<section class="two-column row no-max pad"> <div class="small-12 columns"> <div class="row"> <!-- Primary Column --> <div class="small-12 medium-7 medium-offset-1 medium-push-4 columns"> <div class="primary">

            <?php if ( have_posts() ) : while ( have_posts() ) : the_post(); ?>

              <article class="post">
                <h1><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></h1>
                <h2><?php echo strip_tags(get_the_excerpt() ); ?></h2>
                <ul class="post-meta no-bullet">
                  <li class="author">
                    <a href="author.html">
                      <span class="wpt-avatar small">
                        <?php echo get_avatar(get_the_author_meta('ID'), 24 ); ?>
                      </span>
                      by <?php the_author_posts_link(); ?>
                    </a>
                  </li>
                  <li class="cat">in <?php the_category(', '); ?></li>
                  <li class="date">on <?php the_time('F j, Y'); ?></li>
                </ul>
                <?php if(get_the_post_thumbnail() ): ?>

                <div class="img-container">
                  <?php the_post_thumbnail('large'); ?>
                </div>

                <?php endif; ?>
              </article>                    

            <?php endwhile; else : ?>

              <p><?php _e( 'Sorry, no posts matched your criteria.' ); ?></p>

            <?php endif; ?>

        </div>
       </div>

       <!-- Secondary Column -->
       <div class="small-12 medium-4 medium-pull-8 columns">
        <div class="secondary">
            <h2 class="module-heading">Sidebar</h2>
        </div>
      </div>
   </div>
  </div>

</section>

<?php get_footer(); ?>