Firefox has a feature called “Inspect Element” for inspecting elements on a web page. It allows you to dig deeper in both the HTML and CSS code of a web page and lets you understand the inspected elements position and styling information in the structure. Today, while inspecting the branding features of Johnson&Johnson’s YouTube page, I’ve noticed a “3D” button on the “Inspect Element” bar and found that it takes the experience in a whole new level :)
After a search, learned that it’s been around since de v11 beta and migrated to the v11 stable after testing. If you are interested in learning HTML and CSS, you should try Firefox’s 3D inspection. You can see how browsers implement the code, in a fun way :)