Slider – background

Hello,

I would like to change the background, on which is a title of article on the slider. Now there is something like a shadow (default setting). I would like to “paint” this rectangle on blue color. Where can I do? I checked Appearance -> Editor -> Stylesheet -> #slider part and I don’t know where is it possible.

It is a little hard to explain, I hope you understood me 😉 Thx.

MG