[Theme: Twenty Eleven] Help me with feature image placement!

Hey everyone. I just wanted to put featured image under the post title and date in content.php and content-single.php. I had some codes to put above the the content php code. Just I have a thing that annoying me. It’s the div code that I used outside of the link. I tried to put into the thumbnail php code but my php knowledge is nearly zero. These are the codes:

In my child theme style.css file:

/** THUMBS UP! **/
.thumbnailed { padding-bottom: 1.2em;}

And this is the thing in content.php file:
<div class="thumbnailed"><a href="<?php the_permalink(); ?>" title="<?php the_title_attribute(); ?>" ><?php if ( has_post_thumbnail()) : the_post_thumbnail(); endif; ?></a></div>

Thing just deleted but the same in content-single.php file:
<div class="thumbnailed"><?php if ( has_post_thumbnail()) : the_post_thumbnail(); endif; ?></div>

My site is fthkn.com and also now I am just editing posts to fit to these. I have video posts inside, so the gap between the video and header just annoying. Waiting for if someone helps me, thank you.