CSS Problem

Delete <div style="clear:both;"></div> from the page_spielhalle.php
which you’ll find around this area:

<?php // check if leaderboard is enabled
                    if ( function_exists('myscore_check_leaderboard') ) myscore_check_leaderboard();
                  ?>
                </a>
              </div>
<div style="clear:both;"></div>
       <?php endforeach; ?>

therefore

<?php // check if leaderboard is enabled
                    if ( function_exists('myscore_check_leaderboard') ) myscore_check_leaderboard();
                  ?>
                </a>
              </div>
       <?php endforeach; ?>

Then in your style.css, you should change

.game_title {
float:left;
margin:0 0 0 5px;
padding:0;
text-align:center;
}

to something like one below or change margin/padding to taste

.game_title {
float:left;
margin:0 0 10px 10px;
padding:0;
text-align:center;
}

I tried to use the problem with this solution but it solved the problem only partly.

Every category show 6 posts sorted randomly. If a category have less than 6 posts the list is bad.

You can see it here: https://tiny.cc/11LWT

I solved the problem!

I put to my style.css:

#cat_view h4 {
  padding:  5px 5px 0px 0px;
}  

.cat_link {
  float: right;
  text-align: right;
  font-weight: bold;
  height:  17px;
  width:  600px;
  margin:  7px 5px 0 2px;
  padding-right:  17px;
  background:  url(images/more.png) no-repeat 0 0;
  background-position:  right;
}

It may look good now in Internet Explorer but it’s not looking good in Firefox. Add the <div style="clear:both;"></div> back but this time look below:

<?php endforeach; ?>
            <div class="cat_link"><a href="<?php echo get_category_link($cat_id); ?>">... weitere Spiele dieser Kategorie</a></div>
	<div style="clear:both;"></div>
          </div>
        <?php endif;
      }