LightSlider - is it possible to apply CSS?

Is it possible to apply CSS in the LightSlider in order to change font style and size? Is it possible to add a Fontawsome icon?

I couldn't find any place to do that. Even when trying to style in Markdown (md) file by adding "#" for "h1", etc. it's not applying changes but displaying the symbol. Wondering if it makes sense to dig further or rather to switch to Shortcode Owl Carousel.

Really the best way is to add your own css in your theme. You can create your own lightlslider css file with with whatever customization you like. You can also disable the built-in CSS if that's getting in your way: https://github.com/getgrav/grav-plugin-lightslider

I'm using my own theme, but I could not find the css file in the plugin where I could apply styling on the text inside the slide.