[Resolved] 2 Questions: Headerboarder; Positioning

Hey!
First of all thank you very much for the template I really like it and its very well!

Just for you to know its my first time with wordpress and I own all you addons.

Like the title says I do have two questions:

1. When the screen gets scaled down do lets say smartphone-size the header that has normally no boarders get a white boarder all around is there any way to get rid of that boarder?

2. like you can see in on the homepage http://www.zahnarzt-lorenz.de/wordpress I added some shadows in the menubar… these are *pngs an they fit properly when the window is large but when you scale down the screen slowly they start moving downwards, just by 1 or later 2 pixels, but it looks awful. is there any way to make them stay in place? 😀

Here is the code I embedded in the navigation.php

<nav itemtype="http://schema.org/SiteNavigationElement" itemscope="itemscope" id="site-navigation" role="navigation" <?php generate_navigation_class(); ?>>

      	<div style="position:absolute; z-index:2; left: 50%;margin-left: -520px; margin-top:-12px;"><img src="http://www.zahnarzt-lorenz.de/dropshadow2.png" ></div>
	<div style="position:absolute; z-index:2; left: 50%;margin-left: -520px; margin-top: 39px;"><img src="http://www.zahnarzt-lorenz.de/dropshadow2.png" ></div>
		
		<div class="inside-navigation grid-container grid-parent">
			<h3 class="menu-toggle"><?php _e( 'Menu', 'generate' ); ?></h3>
			<div class="screen-reader-text skip-link"><a href="#content" title="<?php esc_attr_e( 'Skip to content', 'generate' ); ?>"><?php _e( 'Skip to content', 'generate' ); ?></a></div>
				<div class="main-nav">
					<ul <?php generate_menu_class(); ?>>
						<?php 
						if ( has_nav_menu( 'primary' ) ) :
							wp_nav_menu( array( 
								'theme_location' => 'primary',
								'container_class' => 'main-nav',
								'menu_class' => 'menu',
								'items_wrap' => '%3$s'
							) );
						else :
							wp_list_pages('sort_column=menu_order&title_li=');
						endif;
						?>
					</ul>
				</div><!-- .main-nav -->
		</div><!-- .inside-navigation -->
	</nav><!-- #site-navigation -->

Thanks a lot for your help!