Separator after 2 articles with background

I’m having a page for the staff. There always should be 2 members next to each other with name and preview image (thumbnail).
Every second row should have a background image and a background color for the whole browser-width, not only the content-width (image and color is always the same).
See this rudimentary mockup of what I want to achieve:
Image

This is the code for what I have now:

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

                            <div class="half">
                                <h1><a href="<?php the_permalink() ?>" rel="bookmark" title="<?php the_title_attribute(); ?>"><?php the_title(); ?></a></h1>

                                    <a href="<?php the_permalink() ?>" rel="bookmark" title="<?php the_title_attribute(); ?>">
                                        <?php if (class_exists('MultiPostThumbnails')) :
                                            MultiPostThumbnails::the_post_thumbnail(
                                                get_post_type(),
                                                'logo'
                                            );
                                            endif; ?>
                                    </a>

                            </div>

Any help is very much appreciated!