[SOLVED] CSS styling not working

Hello,

I have been trying to change the color of a product title (am using the e-commerce plugin) by styling the css but it doesn't seem to work any way I try to do it. To show an example on my page http://aquilaciencia.es/nuestros_libros/el-ser-humano, I want to change the color of the text "
Nacer y otras dificultades - Francisco González-Crussi", so I look at the html and add the corresponding colour codes to the related "class" in the .css file. Still the text remains white and I can't figure out what else to do. Could you please help me?

Thanks