How to hide the icon for price in a course?

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

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