How to hide the icon for price in a course?

I'm looking to hide the "$ FREE" icon for price in the following image:

http://kunei-listening.com/wp-content/uploads/2015/04/Screen-Shot-2015-04-15-at-12.23.55-PM.png

I added this via CustomCSS but it is ineffective.

.entry-content-excerpt .course-cost {
display: none !important;
}

.quick-course-info .course-cost {
display: none;
}

Is there a way to disable it?

Support access is ACTIVE until April 18, 2015 3:31 am

Thanks very much