The color picker/brightness slider is the Light Entity Card. It’s great because you can choose to have them condensed down like mine or left large. And yes, I love being able to put gaps of set sizes/colours between cards. You can’t tell on those pics, but there’s a blank-card at the bottom of each one, so that there’s a space shown on the ios app.
I really need to look into css, but I currently have enough trouble working with the jinja templates in HA.