Removing page and post titles from Graphene

Hi,

I’m new here and have limited knowledge of Web coding. I’m trying to customize the Graphene theme and remove the page and post titles.

I found a couple suggestions in the forums, and tried them without success. So far I edited the loop.php file by removing:

<h2 class="post-title">
" rel="bookmark" title="<?php printf(esc_attr__('Permalink Link to %s', 'graphene'), the_title_attribute('echo=0')); ?>"><?php if (get_the_title() == '') {_e('(No title)','graphene');} else {the_title();} ?>
<?php do_action('graphene_post_title'); ?>
</h2>

and replacing it with:

<?php if (!is_page()) : ?>
<h2 class="post-title">
" rel="bookmark" title="<?php printf(esc_attr__('Permalink Link to %s', 'graphene'), the_title_attribute('echo=0')); ?>"><?php if (get_the_title() == '') {_e('(No title)','graphene');} else {the_title();} ?>
<?php do_action('graphene_post_title'); ?>
</h2>
<?php endif; ?>

That didn’t do anything. I then tried editing the custom CSS by going to: style.css and inserting:
post-title, entry.title a {display:none;}

Nothing happened. I don’t know if I inserted it in the correct place or if that’s even the correct file.

Can you give me some direction?

Thank you!

I’m sorry. I am very new at this and not a programmer at all. I installed a Custom CSS plugin, but have no idea what code to add to have it hide these items.