Remove posted by, date and no comments

I want to remove the "Posted on July 10, 2013 by admin" text on my posts. I tried to add the .post-by { display: none; } code to my custom CSS, however it does not seem to get rid of it. Even when I clear my cache it still stays. Do I have to make it: #post-by { display: none; }? Not 100% sure how the custom CSS works to override the general code. Here is the custom code I have on my site: #page, #branding { background: none repeat scroll 0 0 rgba(255, 255, 255, 0.8); } #header-right .widget_search { display: none; } #hgroup-wrap { padding: 0; } #site-logo { padding-top: 0; } #hgroup { padding-top: 0; } #hgroup-wrap { padding-bottom: 0; } #single-post-image { display: none !important; } #post-by { display: none; } Here is a link to the site: http://lakeoswegobaseball.net/