My top margin 20 is absorbed by the top margin 40 of my parent
My top margin 60 is absorbing the top margin 40 of my parent, but it is still outside my parent's padding box!
My top margin 10 adds to my parent's padding 10 and does not affect my parent's top margin 40
My top margin 10 adds to my parent's padding box, and does not affect my parent's top margin 40
Despite of empty siblings in front of me, my top margin 20 is still absorbed by the top margin 40 of my parent
