Need a little advice either to look up online or here if able to help

Hello, fellow developers. I have found a cool cssbattle website. I enjoy trying this. it is cssbattle.dev. They challenge to have me do shapes with a div only in css. The challenge site of course blocks their design on html they created for task. There is not a chat and I have tried to look it up online. It wants me to make for of the squares from one they have placed automatically. Is there any advice on what css I need for the div or where I can go to search for myself.

FCC has a course on CSS. There are a lot of youtube videos and blogs. MDN is a good reference. The site css-tricks has good stuff.

In general, do what a developer does - google it.

Already did. I will check out the css-tricks too! Thank you for the new site too, that will be a blast to learn!