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<link rel="author" title="Oriol Brufau" href="obrufau@igalia.com">
<link rel="help" href="https://drafts.csswg.org/css2/#collapsing-margins">
<link rel="help" href="https://drafts.csswg.org/css-sizing-3/#behave-auto">
<link rel="help" href="https://drafts.csswg.org/css-sizing-4/#stretch-fit-sizing">
<link rel="match" href="../reference/ref-filled-green-100px-square.xht">
<meta name="assert" content="
  According to CSS2, the bottom margin of a block container can colla