css classes – how to use it

Hi
It works ! – WOW ! Thank you ! What opportunities do i have with css classe? Can i style the apperance in the SERPS? or on my page? In WP i made all adaptions in style.css – how should i handle css with your plugin? For customizing the FAQ section in the page i think i am fine, but customizing in the SERPS`Is this possible?
best ahmed