[Dilettante_Pro]

<style>
.block_title { display:none; }
</style>
<div class="block_main">
   <div id="block_title" class="block_title">Title</div>
   Block main
</div>
<script src="https://code.jquery.com/jquery-latest.min.js"></script>
<script>
$(function(){											 
   $(".block_main").click(function() {
        $("#block_title").toggle("block_title");
    });
});
</script>