You need not be an expert, but you do need a general understanding of cascading stylesheets (CSS) and how to use a text editor. The snippet goes into the stylesheet of your theme (usually ${Q2A_INSTALL_DIR}/qa-theme/SnowFlat/qa-styles.css). If you're using a different theme than SnowFlat replace the name with that theme's name. But in that case you may also need to adjust the CSS class name.