Hey, I´ve done some exploring and accidentally on purpose managed to alter my sidebars.
I did it by right-clicking on one of my sidebar widgets and ´Inspect Element´. From there I found the applicable code, copied to Edit CSS and changed what I wanted to, then previewed before saving.
This is probably second nature to you guys but completely new to me, I never even knew what Inspect Element meant before just now lol. Anyway, I´m a little bit pleased with myself.
Thank you Tom and bdbrown for helping me so far. You led me to explore an area of website-building I´ve never been before.