So, I'm new to the advancement of fandom pages and I've learned by playing around with the functions, for better or worse. What I can't seem to figure out is how to make a simple border around the infobox "thicker", especially with the new format. I used the infobox builder to create my infobox but it doesn't have color or border thickness included in the visual editor and I'm not sure how to add it to source editing. I know someone said it has to be added to the template, but I'm not sure how? Also, some fandom pages have managed to stretch their background images even after the new update. When I go into my theme designer, it only allows a portion of my image to show with the rest revealing a colored background. How do I make my image fill up the whole page?
Thank you to anyone who is willing to help.
I want to thicken the border and change the background of the infobox so it isn't the same color as the rest of the background, as I've seen on Miraculous fandom page. https://miraculousladybug.fandom.com/wiki/Season_3#International%20releases
I don't know how they did it.