RE: column-span and margin-collapsing (was: [CSSWG] Minutes and Resolutions 2011-09-21)

± ----Original Message-----
± From: Håkon Wium Lie
± Sent: Monday, September 26, 2011 10:11 AM
±
± Also sprach Alex Mogilevsky:
±
±  > ± Spanners collapse vertically, just like these BFC-creating elements  > 
± do:
±  > ± 
±  > ±    <div style="overflow: hidden; margin: 100px 0;"></div> 
±  > ±    <div style="overflow: hidden; margin: 100px 0;"></div>
±  >
±  > But this behavior is different for what one would expect for what  
±  > appeared to be your main use case:
±  > 
±  > 	<h1 style="column-span:all">Title</h1>	
±  > 	<h2 style="column-span:all">Subtitle</h2>	
±  > 	<p style="column-span:all">Abstract...</p>
±
± I don't understand why it's different; in Opera's implementation, collapsing would occur in 
± both examples. And float crossing would not occur in any of them.

H1, h2 etc. are normally not BFC (their margins collapse with child margin and margins collapse trough empty boxes). Then simply adding margin collapsing to external margins of colspan doesn't really create compatibility with single-column flow. 

Alex

Received on Monday, 26 September 2011 18:51:53 UTC