Need to remove quotation marks

I looked at the #13. How to get rid of the quotation marks that surround the random quote?

In your theme’s custom.css or styles.css file write the following CSS.

.testimonialswidget_testimonial .testimonialswidget_open_quote:before,
.testimonialswidget_testimonial .testimonialswidget_close_quote:after {
content: none;
}

I tried both and neither worked. Please let me know if there is another solutions to this problem.

Thank you

http://wordpress.org/extend/plugins/testimonials-widget/