Test case for collapsing margins

Simple sibling collapsing tests:
This has a top/bottom 10px margin
This has a top/bottom 10px margin
This has a top/bottom 10px margin
Simple generational + sibling collapsing tests:
This has a top/bottom 10px margin
This has a top/bottom 10px margin
This has a top/bottom 10px margin
Verify that borders/padding interfere with sibling + generational collapsing:
This has a top/bottom 10px margin
This has a top/bottom 10px margin
This has a top/bottom 10px margin
This has a top/bottom 10px margin
This has a top/bottom 10px margin
This has a top/bottom 10px margin
This has a top/bottom 10px margin
This has a top/bottom 10px margin
This has a top/bottom 10px margin